Police believe the bombers were sent by an Al-Qaeda-linked insurgent group based in Pakistan, and their capture follows widespread rumors that militants were planning attacks in the diplomatic quarter of Kabul.

Heavily armed police stopped the would-be bombers about 7 a.m. at a checkpoint in the southeastern edge of the city as they traveled in an SUV with explosive vests hidden beneath the engine block, according to Abdul Ghafar, deputy commander of the Afghan National Police crisis unit.

Ghafar said police had been given a description of the vehicle and were able to seal off the area. Police said they believed the would-be bombers were headed for a safe house somewhere in the capital to make final preparations for their suicide assault.

“If this team had made it through it would have been a disaster,” Ghafar said.

Police said the five men — ranged in age from 20 to 25 — refused to give their names or nationalities. But authorities were convinced they were sent by the Haqqani group, a Pakistan-based Afghan Taleban faction with close ties to Al-Qaeda.

The five were shown to journalists at a heavily guarded police base on the city’s outskirts, along with their vehicle and bags containing explosive material and suicide harnesses. They stood silently with their backs to the journalists, their eyes covered by blindfolds and hoods and their wrists in handcuffs.

The Haqqani group has been blamed for other attacks in Kabul, including the Oct. 28 assault on a guesthouse used by UN workers. Eleven people were killed, including five UN staff and the three attackers. It may have played a role in the Dec. 30 suicide attack that killed seven CIA employees and a Jordanian intelligence officer at a tightly secured CIA base in Khost province.