President Trump claimed in a Sunday tweet that thousands of undocumented immigrants in Texas jails had "committed sexual crimes against children," which he used to push for a US-Mexico border wall.

The Texas Department of Public Safety did not immediately return Business Insider's request for comment, but reports contradict Trump's portrayal of undocumented immigrants as driving US crime.

Trump pushed for a government shutdown to fund his proposed border wall. The partial shutdown has become the longest in US history.

In pushing for a wall between on the US-Mexico border, President Donald Trump has repeatedly sought to portray undocumented immigrants as a cause of US crime.

The latest effort came in a series of tweets over the weekend, including one on Sunday in which the president said thousands of undocumented immigrants "who have committed sexual crimes against children are right now in Texas prisons" and that most had traveled through the US's southern border.

A report from the right-leaning think tank the Cato Institute based on data from Texas found that fewer undocumented immigrants were convicted of sex crimes than native-born Americans, at an about 8% lower rate, based on 2015 data.

Broadly, "conviction and arrest rates for illegal immigrants were lower than those for native-born Americans," the report, which was issued in late February of 2018 and updated in August, found. "This result holds for most crimes."

Fewer undocumented immigrants were convicted of sex crimes compared with native-born Americans in 2015 in Texas, according to a Cato Institute analysis. Cato Institute

Other analyses have had similar findings.

An article published in the peer-reviewed journal Criminology last year found that where there are more undocumented immigrants in a state, it is linked with "significant decreases" in violence. The data the study relied on included crimes that were and were not reported to the police, and defined violence as rape or sexual assault, among other things.

The Texas Department of Public Safety and an official named John Jones, its division director of intelligence and counter terrorism, who Trump named in his Sunday tweet, did not immediately return Business Insider's request for comment.

In a meeting with Trump Friday, Jones said "In the last 7 years (in Texas), we have over 4,000 people incarcerated that are illegal aliens in Texas jails for sexual assault. The sad thing is 62% of them are sexual assault against children."

If Jones' numbers are correct, the "thousands" that Trump referenced in his tweet are 2,480 to be exact.

The department doesn't generally release numbers of prisoners, an individual at one of its divisions said.

The president's latest tweets come as the ongoing partial US government shutdown officially becomes the longest in the country's history. Trump's insistence on funding for the wall has been the force behind the shutdown.

Read more: The government shutdown enters a record 22nd day as Trump, Democrats continue to battle over the border wall and 800,000 workers go without pay

Trump has used similarly misleading, anti-immigrant rhetoric before, Business Insider has previously reported.

Another tweet from Trump on Saturday about undocumented immigrants and crime used statistics that were "either exaggerated or omitted important context," the New York Times reported.

The Times report pointed to data from Texas showing that of undocumented immigrants who were arrested in the state between mid-2011 and the end of 2018, 3,428 were charged with sexual assault and 2,152 with sexual offenses.

However, there have been fewer convictions, the Texas data shows, with 1,689 of those accused of sexual assault actually being convicted, and 1,148 sexual offense convictions. The report does not make any specific allegations of sexual crimes against children.

Data aggregated by the Texas Tribune shows that in total, 16,287 Texas inmates that have been convicted of aggravated child sexual assault. 11,093 inmates have been convicted of indecent child sexual contact. The Tribune data did not break down the convictions by immigration status.