Chief U.S. District Judge Sherman Finesilver has ordered some of the case documents sealed in a mysterious case involving the arrest of a Utah man with a carload of guns and explosives.

Finesilver handed down the order Thursday to have the plea agreement sealed in the case of Jorge Alejandro of Kaysville, Utah. Alejandro pleaded guilty to one count of illegally possessing an unregistered firearm, a Vietnam-era M-60 machine gun, and 13 other firearms counts were dropped."I am guilty of what's stated here," the soft-spoken Alejandro said. "I received a fair offer from the federal government, and I would like to do everything I can to cooperate and rectify the situation."

The records were sealed at the request of public defender Michael Katz, after Alejandro, 40, told the judge he feared for the safety of his family.

The automatic weapons count carries a possible 10-year prison term and a fine of up to $250,000. Under federal sentencing guidelines, Alejandro, with no previous criminal rec-ord, could be sentenced Oct. 31 to eight to 14 months in prison.

Alejandro was arrested near Limon on June 18 by Trooper Joseph Cullyford of the Colorado State Patrol after the officer had stopped him on westbound I-70. Cullyford became suspicious because Alejandro's sparkling clean 1987 Volkswagen carried dirty Oregon plates. A check showed the plates listed to another vehicle and that the car was stolen in California.

Alejandro told Cullyford there were automatic weapons in the car and it was wired to explode.

He said somebody might be following him and detonate the explosives.

Alejandro said he was taking the cache for an unnamed person to Salt Lake City, where he was to receive further instructions.

Authorities found that some of the weapons had been stolen from Special Effects, a Hollywood company that provides movie props.

Also found were dynamite, blank birth certificates and photocopies of birth and baptismal records.

Alejandro, who spent 60 days in a mental hospital in 1979, had told officers a "very strange story implicating possible government operations," authorities said.