Radical preacher Amritpal Singh, who is on the run following a police crackdown, has been maintaining close links with Pakistani intelligence agency ISI and some terrorist groups based abroad, official sources said on Saturday.

Amritpal Singh, who had even issued a veiled threat to Union Home Minister Amit Shah, has been trying to destabilise the situation in Punjab by indoctrinating and attracting the Sikh youth into the fold of his outfit "Waris Punjab De".

The radical preacher is believed to be a close associate of UK-based Khalistani terrorist Avtar Singh Khanda. Khanda is believed to behind Amritpal Singh's meteoric rise, sources said.

Khanda is a trusted lieutenant of leader of the banned Babbar Khalsa International Paramjit Singh Pamma, who often holds theoretical training classes for the Sikh youth to radicalise them.

The trio have been aiming to destabilise Punjab by ideological indoctrination of the Sikh youth with extremist views, they said.

Khanda gives online demonstrations from Birmingham and Glasgow on how to make improvised explosive devices by using commonly available chemicals.

Amritpal Singh also has links with chief of the International Sikh Youth Federation Lakhbir Singh Rode, who is wanted in India in cases of smuggling of arms and explosives, including RDX, conspiracy to attack government leaders in New Delhi and spreading hatred in Punjab.

When Amritpal Singh was in Dubai, he was in close touch with Rode's brother Jaswant.

The radical preacher was known for asking his comrades to stay armed and he formed a new group called Anandpur Khalsa Army (AKF). This group is always around him with dangerous weapons, they said.

Amritpal Singh, who was a transport operator in Dubai, came in contact with the ISI there, sources said.

The agents of the ISI believed to have told him to motivate the innocent young Sikhs in the name of religion.

After coming to Punjab, at the behest of the ISI, Amritpal Singh tried to spread the influence of his group 'Waris Punjab De'.

Later, he launched a campaign called 'Khalsa Waheer' and strengthened his organisation by going to villages.

He stirred up the issues of Punjab and started inciting the Sikhs against the Government of India. He has been successful in getting people to do what he wanted under the guise of religion and this helped the ISI to carry out its design in Punjab, they said.

Amritpal Singh was anointed the head of the 'Waris Punjab De' following the death of its founder - actor and activist Deep Sidhu - in a road accident in February last year. The event was held at Moga's Rode, the native village of slain militant Jarnail Singh Bhindranwale.

A major police crackdown was underway in Punjab against radical preacher Amritpal Singh and his supporters over charges of spreading communal tension in the state.

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