The co-owner of a catering company that organised events for the US Embassy is among six men detained by Pakistan for allegedly helping the failed Times Square bombing suspect, a Pakistani intelligence official said.

In a statement, the US Embassy warned the catering company was suspected of ties to terrorist groups and said American diplomats had been instructed to stop it.

Like Faisal Shahzad, the Pakistani-American accused over the failed New York bombing, the six Pakistani detainees were all members of their country's urban elite, including several who were educated in the US.

One was a former major who bought his way out of the army because of a "disagreement with its policies", the Pakistani official said.

The suspects were part of a loose network motivated by hatred of America and the west and one of the men often travelled to the tribal areas close to the Afghan border where US officials have said Shahzad received explosives training under the Pakistani Taliban, the official said.

At least two allegedly helped Shahzad with funding, the official and another Pakistani security officer said, although the exact nature of their link to the Times Square bombing suspect was still being investigated.

The co-owner of the Hanif Rajput Catering Service, Salman Ashraf Khan, was recruited because two other suspects "wanted him to help bomb a big gathering of foreigners" whose event his company was catering, the intelligence officer said.