The number of asylum seekers who illegally crossed the U.S. border into Canada more than tripled last month, according to Canadian government data released on Thursday, as migrants worried about the U.S. administration's immigration crackdown head north.

More than 3,100 people walked across the border illegally in July to file refugee claims and were arrested, up from 884 in June, the federal government said.

Ninety-six percent of them went to Quebec, where an influx of asylum seekers, primarily Haitians, is sparking a backlash from opposition politicians and anti-immigrant groups in the primarily French-speaking province.