Close to 350,000 convicted immigrants are still at large in the US, according to an immigration research organisation.

Data obtained by the Centre for Immigration Studies (CIS) from the US Immigration and Customs Enforcement (ICE) dated March 2 and provided to Breitbart News showed that there were 168,680 convicted criminal immigrants with final orders of deportation but remained at large in the US.

In addition, 179,018 convicted criminal immigrants with pending deportation cases are also at large.

Under the Obama administration, 36,007 immigrants with nearly 88,000 convictions were released in 2013. The convictions included 193 for homicide, 426 for sexual assault, 303 for kidnapping, and 1,075 for aggravated assault.

Last month, Senate Judiciary Committee Chairman Chuck Grassley, Immigration and the National Interest Subcommittee Chairman Jeff Sessions and Judiciary Committee member Jeff Flake asked ICE to explain about cases of undocumented immigrants with criminal records and facing deportation that were released from custody and committed new crimes.

ICE confirmed that 12 convicted criminals are now facing homicide cases after being released from government custody instead of being deported.

The agency also said that 36,007 criminals were released from its custody in 2013, and 1,000 of them have since been convicted again of additional crimes.

Of those repeat offenders, 156 were released from ICE a second time instead of being deported.

Senators have asked ICE Assistant Secretary Sarah Saldaña to provide more information about the criminals.

Grassley's statement said what's happening is contrary to what President Obama said last November about his executive immigration actions in which he pointed out that "we're going to keep focusing enforcement resources on actual threats to our security—Felons, not families; criminals, not children; gang members, not a mom who's working hard to provide for her kids."