As RJD chief Lalu Prasad and his family faced more heat from central agencies in the alleged land-for-jobs scam, the ED on Saturday said it seized Rs one crore in "unaccounted cash" and detected proceeds of crime worth Rs 600 crore after raids against them in a related money laundering case.

An investigation is underway to unearth more investments made on behalf of Prasad's family and their associates in various sectors, including real estate, the Enforcement Directorate said, a day after it swooped down on multiple premises including the one linked to RJD chief's son and Bihar Deputy Chief Minister Tejashwi Yadav in Delhi.

Tejashwi Yadav was called for questioning on Saturday by the Central Bureau of Investigation (CBI) in the case but did not appear and has sought a fresh date citing personal reasons, officials said.

The agency had recently quizzed Lalu Prasad and his wife Rabri Devi -- former chief ministers of Bihar -- in the case.

It is alleged that people were given employment in the railways in return for land parcels gifted or sold at cheap rates to the Yadav family and its associates during Prasad's tenure as the railway minister in the UPA government from 2004 to 2009.

In a statement on Saturday, the ED said, "Searches resulted in the recovery of unaccounted cash of Rs 1 crore, foreign currency including USD 1,900, 540 gms gold bullion and more than 1.5 kg of gold jewellery worth about Rs1.25 crore." "Several other incriminating documents including various property documents, sale deeds, etc. held in the names of family members (of Lalu Prasad) and benamidaars indicating illegal accretion of huge land bank and electronic devices," it said.

It said the raids resulted in the "detection of proceeds of crime amounting to about Rs 600 crore at this point of time which is in the form of immovable properties of Rs 350 crore and transactions of Rs 250 crore routed through various benamidaars".

Making a specific mention of Tejashwi Yadav, the ED said it is suspected that a huge amount of proceeds of crime has been infused in purchasing the property situated at D-1088, New Friends Colony in south Delhi.

It is an independent 4-storied bungalow registered in the name of A B Exports Private Limited but is being used by Tejashwi Yadav as his residential premises.

This company has been called a "beneficiary firm" in this case and is "owned and controlled" by Tejashwi Yadav and his family, the ED said.

This house was shown to have been acquired at a value of a mere Rs 4 lakh while the present market value is approximately Rs 150 crore, the agency said.

While other opposition parties have slammed the action by central agencies and accused the BJP-led central government of political vendetta, RJD ally and Bihar Chief Minister Nitish Kumar on Saturday said it was a repeat of what happened in 2017 when he was in the anti-BJP camp.

"What do I have to say, those who are at the receiving end are giving an adequate response... similar things had happened in 2017 when I was on this side (in the anti-BJP camp). Now that I am here again, these things are happening again," said Kumar when asked about his silence on the issue.

This was in contrast to the stand Kumar took in 2017, when he had wanted the ally to come clean on charges of corruption.

Congress leader Priyanka Gandhi Vadra alleged that the BJP-led government is indulging in politics of "suppressing" the unyielding voices of the Opposition.

"The action of agencies on Bihar Deputy Chief Minister Tejashwi Yadav ji is inspired by this politics," the Congress general secretary alleged.

"The public is watching everything, and will take all this into account," she said.

After the recent questioning of his parents, Tejashwi Yadav had alleged that investigation agencies were acting against political opponents of the ruling BJP at the Centre.

On Saturday, the ED, in its statement, said that Tejashwi Prasad Yadav was found to be staying at the New Friends Colony house during the raid and was found to be using this house as his residential property.

"It is suspected that huge amount of cash/proceeds of crime has been infused in purchasing this property and few Mumbai-based entities, dealing in the gems and jewellery sector were used to channel ill-gotten proceeds of crime in this regard," the ED alleged.

"The property has been though, on paper, declared as an office of A B Exports Private Limited and AK Infosystems Pvt ltd, it is being exclusively used as residential premises by Tejashwi Prasad Yadav, son of Lalu Prasad Yadav," it said.

The agency said its probe found that four parcels of lands acquired by the family of Lalu Prasad in just Rs 7.5 lakh from poor Group-D applicants were sold to Syed Abu Dojana, ex-RJD MLA, by Rabri Devi with huge gains at Rs 3.5 crore in a "collusive" deal.

The probe found that a major portion of the amount thus received, was transferred to the account of Tejashwi Prasad Yadav, it said.

Investigations revealed that in a similar fashion, lands were taken from several poor parents and candidates for Group D jobs in the Railways.

"It has been revealed during the investigation that in many Railways Zones, more than 50 per cent of recruited candidates were from Lalu Yadav families' constituencies," it said.

The investigation is underway to unearth more investments made on behalf of Lalu Yadav's family and their associates in various sectors, including real estate at various places, the ED said.

The agency added that while carrying out the searches, all legal formalities were fully observed and due courtesy was extended to the women, children and the senior citizens present at the search premises.

In a video statement, RJD Rajya Sabha MP Manoj Kumar Jha has alleged that Tejashwi Yadav's "pregnant wife was taken ill with high blood pressure" because of the ED raids and warned that the people of Bihar will take to the streets.

The CBI has filed a charge sheet in the land-for-jobs case against Prasad, Rabri Devi and 14 others under charges of criminal conspiracy and provisions of the Prevention of Corruption Act, and all the accused have been summoned on March 15 by a special court, officials said.

The allegations have been denied by members of the Yadav family.

The CBI officials said the fresh round of questioning is taking place as part of "further investigation" on the basis of fresh inputs gathered by it during its ongoing probe.

The agency has alleged that during Lalu Prasad's tenure as the railway minister in the UPA government from 2004 to 2009, favourite candidates were appointed in the railways in violation of norms and procedures.

No advertisement or public notice was issued for the appointment but some residents of Patna were appointed as substitutes in different zonal railways located in Mumbai, Jabalpur, Kolkata, Jaipur and Hazipur, the CBI has alleged.

As a quid pro quo, the candidates, directly or through their immediate family members, allegedly sold land to the family members of Prasad at highly discounted rates, up to one-fourth to one-fifth of the prevailing market rates.