Two Government ministers who missed a crunch vote on Syria which led to a shock defeat for David Cameron were reportedly in a soundproof room near the Commons and missed the bell to vote.
International Development Secretary Justine Greening and Foreign Office Minister Mark Simmonds failed to return to the division lobbies for the second vote on military intervention in Syria last night - a vote the Government lost by 13.
The Prime Minister said that he had accepted apologies from the pair, who were among 10 members of the Government's so-called payroll vote who failed to make it to the Commons lobbies.
Asked about their absence, Mr Cameron said: "This was a technical issue. They had made it for the first vote, they were in a room in the House of Commons where they didn't hear the division bell. They missed the vote.
"They have apologised profoundly, I have accepted that apology. It wouldn't have changed the result."
It is understood that Ms Greening and Mr Simmonds were in a room near the Commons chamber, discussing the situation in Rwanda, when the vote was called.
Both MPs voted against the Labour amendment at 10pm, which called for "compelling evidence" that the Assad regime was behind the chemical attack.
But Africa Minister Mr Simmonds then apparently asked to speak to Ms Greening and the pair went to a small meeting room near the chamber which ministers often use between votes.
Once there, they apparently did not hear the bell for the second vote.
The room is reported to be the Reasons Room, directly behind the Speaker's Chair, close to where the doorkeepers shout "Division" in a loud voice. A House of Commons spokesman said it was a "solidly constructed room with a well-fitting door".
Among the other missing Government members, four - Treasury Minister David Gauke, International Development Minister Alan Duncan, Pensions Minister Steve Webb and whip Jenny Willott - did not break from their holidays abroad, all with permission from the whips office.
Mr Gauke said: "I'm supportive of the Prime Minister's position on this. I was set to come back when the whips contacted me to say they had managed to arrange a pair.
"If I had come, then another Labour MP would have come back too."
Cabinet minister without portfolio Ken Clarke had "logistical family reasons" for missing the vote but insisted he backed the Government.
Liberal Democrat Lorely Burt, a parliamentary private secretary (PPS) to Chief Secretary Danny Alexander, abstained after speaking out against military action during the Commons debate.
Tory whip Mark Hunter and Liberal Democrat PPS Tessa Munt also missed the vote for unknown reasons.
A House of Commons spokesman said: "Both divisions proceeded as normal last night, with division bells and the usual audio/visual indications on the hundreds of monitors around the estate.
"The division bells have been tested this morning and are working correctly."
The Commons spokesman added: "There would have been a lot of activity there around those (meeting) rooms.
"I think it would have been clear that there had been a division on and those involved would have known there was a division on as well."