SAN FRANCISCO, June 9: An investigation into an alleged Al Qaeda cell in the city of Lodi, in which a man and his son and two Muslim religious leaders were held earlier, widened on Wednesday with the arrest of another Pakistani.

A US immigration and customs enforcement official said Mohammad Hassan Adil, 19, was detained on Wednesday for violation of immigration rules. He is son of Mohammed Adil Khan, who was recently taken into custody along with Lodi mosque Imam Shabbir Ahmed under same charges.

“He’s being held on administrative immigration violations,” immigration department spokeswoman Virginia Kice said about Hassan Adil.

US authorities declined to say whether more arrests would follow. “This is an ongoing process that will continue for some time,” Attorney McGregor Scott told a press conference.

He reiterated that the investigation had not uncovered any specific threat or danger to the general public.

He said the next few days could be crucial as federal and state investigators sift through evidence seized during raids by the FBI on Tuesday on the mosque and the homes of 47-year-old Umer Hayat and his son, Hamid Hayat, 22. The two were arrested as part of an investigation by the FBI into possible connections with Al Qaeda.