PM Brown wins vote on terror law
Thirty-six Labour MPs joined forces with Conservatives and Lib Dems to vote against the proposals.
But that was not enough to defeat them - although the government still faces a battle in the House of Lords.
The 42-day proposal was passed by 315 MPs to 306 - with votes by the nine DUP MPs proving crucial.
Six SNP MPs also voted against the proposal, as did three Plaid Cymru MPs and three from the Northern Ireland-based SDLP.
The Tories and Lib Dem MPs accused the DUP of 'selling out.'
Labour rebels claimed the DUP had obtained guarantees that the government would block efforts to use the Human Embryology and Fertility Bill, currently going through Parliament, to loosen abortion rules in Northern Ireland.
They are also said to have cut a deal to keep revenue from water rates, which Westminster had been set to claw back.
But the DUP denies it was promised any financial support and insists it voted out of principle.
DUP MP Rev William McCrea said: "The issue was on national security."
Northern Ireland Secretary Shaun Woodward told the BBC: "There was no deal. There is no deal. They decided on principle. They made up their own minds."