U.S. Customs and Border Protection agents found 40 illegal immigrants from Brazil in a truck's trailer in Falfurrias, TX, on Saturday, Feb. 17.

According to The Associated Press, none of the immigrants had been hurt - but the inside of the trailer was so hot that when agents opened the doors, they could feel a rush of heat.

Falfurrias, which is 75 miles north of the border on U.S. 281, has an inland highway checkpoint.

Agents searched the trailer after a border patrol dog picked up the scent of people inside.

The name of the truck driver hasn't been released, but authorities said in a press release that the driver is a U.S. citizen from Weslaco, TX.

The discovery comes less than a month after a Texas jury sentenced former trucker Tyrone Williams to life in prison for his part in a 2003 smuggling operation that resulted in 19 deaths.