Rubio, Cruz attack Trump in GOP debate

Thursday's Republican debate in Houston, Texas, played out as a raucous night of tit-for-tat insults, with candidates shouting over one another so much that it was hard to follow at times.

The debate, which is the last before "Super Tuesday" on 1 March, where 11 states will hold republican primaries, is seen as a crucial platform to make a last minute appeal to republican voters.

The mission for Florida Sen. Marco Rubio and Texas Sen. Ted Cruz was clear: to defeat billionaire frontrunner Donald Trump who has already won three out of the four primary and caucus contests held and continues to lead in the polls.

A fiery Rubio went hard after Trump, attacking his position on immigration, his privileged background, his speaking style and more.

When Trump faulted Rubio on a deal to buy a $179,000 house, the Florida senator shot back that if Trump "hadn't inherited $200 million, you know where Donald Trump would be right now? Selling watches in Manhattan."

Ted Cruz piled on, too, questioning the billionaire's conservative credentials, as the two senators tag-teamed Trump in a debate that reflected the increasing urgency of their effort to take down the businessman before he becomes unstoppable.

It was a rare night where the bombastic Trump found himself on the defensive.

The other two remaining candidates, Ben Carson and John Kasich, were largely left to watch the fireworks flying overhead.

Both Rubio and Cruz said that Trump was fined a $1 million hiring illegal immigrants to work on his constructions contracts.

However, Rubio was the principal aggressor of the night, and he held nothing back.

Taking on Trump's declaration that he would build a wall on the Mexican border, Rubio declared: "If he builds a wall the way he built Trump Tower he'll be using illegal immigration to do it."

In the past, Rubio and Cruz had shown little willingness to take on the former reality television star when the national spotlight was the brightest.

However that all changed on Thursday night, clearly showing the growing sense that Trump is on track for the republican party nomination.

Agencies contributed to this report