A Salt Lake County jail inmate — accused of killing an exchange student at the University of Utah — has reportedly been making weapons in his cell and hiding them well enough to get them past the jail’s full-body scanner.

Austin Boutain, 24, was taken to the hospital for an X-ray after he told jail staffers that he had a metal weapon.

Boutain is accused of fatally shooting ChenWei Guo in the foothills behind the U., setting off a 14-hour manhunt before his Oct. 31 arrest at the Salt Lake City Main Library.

He was charged in 3rd District Court with aggravated murder and a dozen other felonies, including aggravated assault for allegedly attacking a fellow inmate.

In his nearly five-month history at the Salt Lake County jail, Boutain has been accused of hiding weapons — such as a screw he put in his nose — that he fashions out of items at the jail.

He has reportedly used the weapons to assault a prisoner, escape from his handcuffs and hurt himself, according to a recently unsealed affidavit for a search warrant.

On March 5, Boutain reportedly “brandished” a weapon inside his cell.

The next day, a lieutenant asked the inmate whether he had a weapon, the affidavit states, and Boutain admitted that he did.

But he didn’t hand it over.

“I can’t,” he reportedly told the lieutenant, according to the affidavit.

Boutain told them that the weapon was metal, and that he had discovered a way of concealing it from a full-body scanning system that the staff uses.

Jail staffers scanned him for a weapon multiple times before finding something.

The inmate had clenched the muscles in his buttocks, which caused a dark area on the scan and hid foreign objects, according to the affidavit.

Boutain was told that he could either remove the object or be transported to the hospital, where medical personnel would take it out for him. Boutain said he wouldn’t comply.

He intended to stab and kill deputies with two footlong “shanks” he carved from a recreation yard door, according to the affidavit. One of the shanks was found. The other, as of the March 6 affidavit, wasn’t.

Intermountain Medical Center personnel declined to comply with the warrant because it did not specify “without consent.”

A Salt Lake County jail spokesman declined to comment on whether jail staffers have recovered anything from Boutain, citing medical privacy and an ongoing investigation.

Boutain and his wife, Kathleen Boutain, 24, are accused of driving to Utah in a stolen truck after allegedly killing a man in Colorado. In the foothills behind the U., according to court documents, they planned to kidnap someone with a car, hold the driver hostage while he or she drove the Boutains to Tennessee, then kill the victim.

Just over two months after Boutain’s arrest, prosecutors filed additional charges: aggravated assault and possession of items prohibited in a jail, both second-degree felonies. In January, he allegedly attacked a fellow inmate with sharpened nail clippers.

Kathleen Boutain is not facing murder charges, but she is accused of criminal solicitation and theft by receiving stolen property.