The Congress on Saturday demanded a probe by the Central Bureau of Investigation (CBI) into the alleged murder of Haryana BJP leader Sonali Phogat claiming the police were trying to hush up the matter.

Phogat died in Goa on Tuesday under mysterious circumstances following which two men, including her personal assistant, who had accompanied her to the coastal state are arrested on the charge of murder by the state police.

"Many politicians said that her death was due to a heart attack. But finally, it has been revealed as murder. There is more to this murder than meets the eye and every angle needs to be investigated. These kinds of cases need to be investigated by the CBI to unravel the truth," Goa Leader of Opposition Michael Lobo told PTI.

On August 25, the Goa police arrested two persons and charged them with murder in connection with the death of Haryana-based Bharatiya Janata Party (BJP) leader Sonali Phogat, an official said.

The two, Sudhir Sagwan and Sukhwinder Wasi, are said to be associates of Phogat (42), who was brought dead to the St Anthony Hospital in Anjuna in North Goa district on August 23 morning.

Deputy Superintendent of Police (Mapusa) Jivba Dalvi told PTI that both the accused have been arrested under murder charge.

Sagwan and Wasi had accompanied Phogat when she arrived in Goa on August 22.

BJP leader Sonali Phogat was fed some "obnoxious chemical" through her drinks by the two accused during a party at a North Goa restaurant which apparently caused her death, police said.

The motive behind her murder could be "economic interest", said a senior police official.

The incident took place at Curlies Restaurant at Anjuna in North Goa district on the intervening night of August 22 and 23, Inspector General of Police Omvir Singh Bishnoi said.

Sagwan and Singh confessed during questioning that they had intentionally mixed the substance in her drinks, he said.

The two men were seen taking Phogat to the washroom of the restaurant around 4.30 am on August 23 and the three of them were inside the washroom for two hours, he said.

Custodial interrogation will throw light on what happened during those two hours, Bishnoi added.

Two other women were also with the accused at the party and were seen cutting a cake, he said, adding that both were being questioned. Asked about the "multiple blunt force injuries" on her body mentioned in the post-mortem report, Bishnoi said as per the accused these could have been caused by abrasion while she was being taken to the hospital.

When she was taken to the hospital, there were no visible injuries, hence the doctors suspected that she died due to a heart attack, the IGP said.

But Phogat seemed to have actually died due to the substance she was fed at the restaurant, he said.

Police will also record the statement of taxi drivers who ferried her from Curlies restaurant to the hotel where she was staying and later to the hospital, Bishnoi said.

More people were supposed to join Phogat and others from Mumbai, the police official said.