There were two separate walkouts at Toronto detention centres Wednesday, including one involving black guards who say they've been receiving threatening, racist letters from colleagues.

About 30 guards at the Toronto Jail, formerly known as the Don Jail, walked out early in the day, saying the letters have been sent to black guards for the past three years and nothing has been done.

For a while, the letters had stopped, but in the last couple of of weeks they began again. They're anonymous letters laced with violent, racist language and threats of death that have been found in workplace mailboxes and are allegedly sent by fellow employees.

Jail guard Hayden Morrison received a letter and decided it was time for action. Morrison said there's no doubt the letters are directed at black jail guards.

"They've said things like they want all the 'n-ers' out of this jail, they want all the 'n-ers' dead, they want all the 'n-ers' just to get their own jail. Those are some of the things that they said. As vile as you can think," said Morrison.

"Honestly, if somebody said, 'Welcome to 2008' based on this, I thought it was 18-something and in the deep south."

The guards' union said it will do whatever it can to help in the investigation.

"Harassment and racism in any form will not be tolerated by this union," Warren Thomas, the president of the Ontario Public Service Employees Union (OPSEU), said in a news release.

"We will assist in any way possible to ensure that those who perpetrate this type of criminal behaviour are identified and dealt with by the proper authorities."

The officers said they have been promised action but nothing has changed.

A spokesman for the Ministry of Community Safety and Correctional Services said two separate investigations are underway — one by the ministry and one by Toronto police.

Guards at the Toronto Jail said they will return to work when they feel their health and safety isn't at risk.

Meanwhile, about 80 guards and staff at the Toronto West Detention Centre also walked out on Wednesday in an apparent dispute over video cameras that are being used to monitor staff.

Community Safety and Correctional Services Minister Rick Bartolucci said "everything is under control" and that he expects the issues to be resolved soon.

Bartolucci said he is not considering an injunction to force the workers to return to their jobs.