Gary Allen Land and Robert Jacks were arrested at dawn in a motel at Carthage, Missouri, about 250 miles north-east of Oklahoma City. Jacks is said to be in his 50s, but Land is aged 35 and bears a strong physical resemblance to the portraits of the second suspect issued by the authorities after the bombing.
Like John Doe No. 2, the quarry of the biggest US manhunt in decades, Land is tanned and powerfully built. As the FBI description of him suggested, he also lifts weights. He does not, however, have a tattoo on his arm, as was claimed in the initial identikit on 21 April.
At a White House briefing, the Attorney General, Janet Reno, said Land and Jacks were "co-operating" with investigators. In sharp contrast to McVeigh, 27, who claims to be a political prisoner and refuses to answer questions, Land and Jacks have agreed to be interviewed and have permitted their property to be searched.
Like McVeigh, both men lived for a spell in Kingman, Arizona, now a focus of investigators who have questioned a former army colleague of McVeigh, Michael Fortier. Life in the remote high desert city on the old Route 66 seems to have been drab and aimless. Neighbours of Jacks and Land yesterday remembered them as "weird, they just sat around drinking".
But last month they drove to Oklahoma, and on the day of the bombing they are believed to have checked in to a motel in Perry, 60 miles north of Oklahoma City, where McVeigh was taken into custody for a traffic and firearms offence barely an hour after the explosion.
The key to what may prove a vital break in the worst ever terrorism case on US soil was their car. The white 1981 Thunderbird, registered in Land's name and carrying Arizona number plates, has been placed by witnesses near the Alfred P Murrah building in Oklahoma City shortly before the explosion.
Acting on an FBI alert, Missouri state patrol officers spotted the vehicle on Monday outside the motel, where Land and Jacks were arrested at 6.45am the next day. Both were due to appear before a federal magistrate late yesterday.
Two other friends of McVeigh, the brothers Terry and James Nichols, are also in custody, but on explosives charges thus far not directly related to the Oklahoma City bombing. James Nichols, detained on 21 April at his farm in Michigan, was due to go before a bail hearing yesterday.
The official death toll of the disaster has now risen to 146 and rescuers say around 20 people are still unaccounted for.