The prime accused in the e-mail threat to BJP leader L K Advani was on Friday remanded in 14 days police custody even as two separate police teams from Assam and Meghalaya started investigations into the case.

The CJM Court in Shillong remanded Mominul Haque to 14 days police custody.

 IG (special branch) S B Singh said he was being interrogated and his revelations and other facts were being corroborated to ascertain whether he had any links with the Indian Mujahhidin group.

"Prime facie it appears that he had sent the email out of religious emotion...but we will have to investigate more," Singh said.

A special team from Assam police also held a meeting with officials from the state and were scheduled to interrogate him.

An official in the Assam police said the top security brass of the neighbouring state also had a separate security meeting at Guwahati to oversee the arrangements for Advani's security, during his two-day visit to Assam and Meghalaya.

 "We are taking the matter seriously, and are leaving no stone unturned to ensure security to Advani," he said.

Mominul confessed to have sent the email to local newspapers here in the name of Indian Mujahhidin, threatening to eliminate Advani during his Shillong visit on September 29.