DHAKA: The family of the young Bangladeshi man accused of plotting to blow up the New York Federal Reserve said Thursday they had been questioned by police.

Quazi Mohammad Rezwanul Ahsan Nafis, 21, was arrested Wednesday in Manhattan after he tried to detonate what he thought was a live bomb, but was actually a dummy provided in a sting operation, federal prosecutors in Brooklyn said.

Bangladesh police visited Nafis's home in a southeastern neighbourhood of Dhaka Thursday afternoon and questioned family members over his activities in Bangladesh and the United States, his brother-in-law told AFP.

Tawfiq Alam Siddiqui said that between seven and eight plain-clothed officers from the detective branch of the police quizzed Nafis's parents, sister and other family members.

“They asked where did he live in the US and where did he study in Bangladesh and the US and some other things,” he said, without giving further details.

Masudur Rahman, a senior official in Dhaka Metropolitan Police's detective branch, confirmed to AFP that officers had visited Nafis's house.

“We are investigating whether Nafis... was involved with any militant group or activities,” he said.

“We quizzed his parents and so far we have a decent idea of his educational background.”He added US law enforcement agencies had not yet contacted Bangladesh police.

Authorities in New York allege Nafis, whose father is the vice president of a bank, travelled to the US with “the purpose of conducting a terrorist attack”and sought out Al-Qaeda contacts after his arrival.

Mokhlesur Rahman, head of Bangladesh's Rapid Action Battalion, a security branch tasked with tackling Islamic militancy, said Nafis had never before come to the attention of the national intelligence services.

“Nafis is not on our list” of Islamic militants who operated in the country, he told AFP.

“We are still trying to get more information.”Nafis has allegedly written a statement claiming responsibility for the plot in which he said he wanted to “destroy America” and referred to slain al Qaeda founder Osama bin Laden as “beloved”.