A U.S. judge voiced concern that it would be risky to end electronic location monitoring for two engineers awaiting criminal trials on charges they stole trade secrets from Apple Inc.’s autonomous-driving project for new jobs in China.

U.S. District Judge Edward Davila seemed skeptical at a hearing Monday of a recommendation by the office that supervises defendants on bail to discontinue monitoring for the two men in light of their compliance with other conditions of their release.

“I do have continued concerns about their release from location monitoring,” the judge told lawyers. He didn’t issue an immediate ruling.

Prosecutors previously said a search of the Maryland home of one of the ex-Apple engineers turned up a classified file from the Patriot missile program that belonged to his ex-employer, Raytheon Co.

“The government fears that if the conditions of location monitoring are removed these defendants will flee and once they are gone, they are gone,” prosecutor Marissa Harris told the judge Monday.