The two men charged Monday for threatening an attack on the Pokemon World Championships in Boston boasted about their plans online, police said.

Kevin Norton, 18, and James Stumbo, 27, both of Iowa, were held without bail pending a Sept. 1 dangerousness hearing for what authorities have called serious threats against the competition, which was attended by thousands, many of them children. 

Police reportedly found two high-powered firearms, a pile of ammunition and hunting knife on Friday in a vehicle they were driving. The pair were arrested in a Saugus hotel room Saturday, police said.

“Inside, there were a lot of kids,” Boston Police Commissioner William Evans told reporters Monday morning. “Thank God we were able to cut off whatever these two individuals coming from Iowa were up to.”

After receiving tips from convention center authorities – who first were tipped off by Pokemon leadership - stopped the pair as they tried to enter the Hynes Convention Center on Thursday, police said. Police released the two and seized their car pending a search warrant, then arrested the men in a Saugus hotel room Saturday, police said.

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A Facebook user with Stumbo's name posted this images of weapons on a vehicle and this message: "Kevin Norton and I are ready for worlds Boston here we come!!!"

A Facebook user with Stumbo's name posted this images of weapons on a vehicle and this message: "Kevin Norton and I are ready for worlds Boston here we come!!!"

Evans on Monday could not say whether the two were being monitored by police during the time they were released from custody. He said police believed the threat had been neutralized when officers seized the weapons, and added the men had not yet checked into the Saugus Red Roof Inn when their vehicle was impounded.

Messages online from the suspects included references to “bullet holes” and “creating another Boston Massacre,” authorities said, as well as nods to the Columbine High School shootings.

“There were alarming social media posts, specifically Facebook forums, relative to threats of violence at the Pokemon World Championship,” Suffolk County Assistant District Attorney Joseph Janezic said before praising law enforcement at the Monday arraignment.

Prosecutors said that Stumbo posted a status update saying “My AR-15 ‘you lose.’” Norton has photos of him firing guns on his Facebook page, officials said.

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Defense Attorney Steven Goldwyn said that the charges against Stumbo all pertain to possession, which he said did not qualify as probable cause for arrest because he was not in control of the car. 

Weapons seized from the vehicle the suspects were driving, according to police.

Weapons seized from the vehicle the suspects were driving, according to police.

Boston Police Department

Photo:

“The firearms were not found on his person,” Goldwyn said. “He was not in possession of the firearms or the ammo and does not own the car.”

The two are said to have traveled to Boston from Iowa with a 12-gauge Remington shotgun and 244 shells, and a DPMS Model AR-15 assault rifle with a high capacity clip and a scope as well as 40 rounds, as well as a hunting knife in the car.

Neither men have criminal records. Norton and Stumbo stood in court wearing gym shorts and T-shirts. Norton had a camouflage hunting shirt on. 

The two were arraigned on possession of unlicensed firearm charges, and have not yet faced charges for the alleged threats.