Royal Canadian Mounted Police are stepping up their search for a suspect who may be displaying 'erratic behaviour' after a pair of mail bomb attacks in Kelowna, British Columbia.

On Monday, two people suffered minor injuries when a package containing a home-made bomb exploded while they were opening it.

The two were bruised and their clothes were charred, but they didn't require medical attention.

Last Friday, a bomb was delivered by mail to Kelowna's regional health unit. Police were able to destroy the bomb without incident, but so far no group or individual has claimed responsibility.

There was speculation the first mail bomb was linked to the opening of abortion services at the Kelowna General Hospital.

But authorities say the latest victims aren't connected in any way to the health unit, or to any pro-choice or anti-abortion group.

The RCMP is warning residents, especially medical staff, not to open any suspicious packages.

Canada Post is also scrutinizing packages in the mail. We have advised all our staff in the whole of the Okanagan about security procedures with regard to any suspicious-looking packages, said Canada Post spokesperson Bob Taylor.

We want to ensure that we don't have any incidents involving our staff and, or our customers. That's our main concern.