Police have charged an inmate at the Whitehorse jail with arson after a fire was set in one of the segregation cells Thursday afternoon.

Another inmate has been charged with assaulting the guards who were trying to remove him from his cell as it filled with smoke.

David Geoghegan, 19, has been charged with arson endangering life.

Michael Nehass, 25, is charged with four counts of assaulting a peace officer.

Whitehorse RCMP believe the fire was set around 3:30 p.m. yesterday.

Jail staff detected the smoke. While attempting to remove the men from the side-by-side segregation cells, four guards were assaulted, according to information filed by police Thursday.

Nehass has a record of assaulting officers in the jail.

He pleaded guilty to assaulting a guard in July 2008 and then again in October.

He was also convicted of setting a fire in his cell and threatening to kill one of the jail staff in October 2008. Initial reports from police indicate Nehass is not suspected of starting this fire.

Both Nehass and Geoghegan were briefly taken to Whitehorse General Hospital and treated for smoke inhalation.

Several guards also received medical attention for smoke inhalation, according to police.

None of the guards who were assaulted sustained any serious injuries, police spokesman Sgt. Don Rogers said today.

A number of inmates were evacuated because of the fire, but most residents of the jail were unaffected, said Department of Justice spokesman Dan Cable.

The fire did not get out of hand, and was quickly put out by firefighters who were at the jail within minutes of the blaze being spotted.

There was minimal damage to the two segregation cells, Cable said, and both have already been cleaned up.

Police are still investigating how the fire was started, and declined to give any further details.

Geoghegan is currently serving a sentence for possession of a stolen vehicle. He was arrested and charged with the crime in Carmacks last month.

Justice officials would not say why the two men were being kept in segregation.

Generally, inmates are put into the single rooms because of bad behaviour or as a safety measure for themselves, the other inmates or the guards.