US officials have made almost 200 arrests and seized more than $625,000 in illicit profits in a month-long crackdown on human smuggling.

It comes in response to an influx of illegal immigrants into Texas, the Department of Homeland Security said yesterday.

Homeland Security Secretary Jeh Johnson said the campaign underscored the government's pledge that US borders were not open to illegal immigration.

He said that if a person enters the United States illegally, they will be sent back.

"Equally important, those who prey upon migrants for financial gain will be targeted, arrested, and prosecuted," Mr Johnson added.

Mr Johnson said the government sent extra personnel to Texas' Rio Grande Valley in late June to combat human smuggling operations on the southwest US border.

The Obama administration has been seeking to deal with a surge of undocumented children across the southern border.

During the nine months ending 30 June, more than 57,000 children were detained at the US-Mexico border, most from Central America.

This figure is double last year's count, according to US government data.

President Barack Obama will meet the leaders of Honduras, Guatemala and El Salvador on Friday to discuss cooperation in dealing with the flow of child migrants.