Hamilton police are investigating after two suspicious packages were found in mailboxes on Main Street East Friday.

Officers have closed of a stretch of Main Street from the Queenston Traffic Circle to Ottawa Street North.

Staff Sgt. Scott Moreton told CBC News that two suspicious packages were found in two separate Canada Post mailboxes.

Moreton could not say exactly what the packages looked like.

A bomb squad robot was used to detonate one of the packages in the interest of public safety, he said, adding that there is currently no threat to the public.

Moreton could not yet say if the package itself was any sort of explosive.

<a href="https://twitter.com/hashtag/HamOnt?src=hash">#HamOnt</a> Bomb squad at work. <a href="https://t.co/nVEAfywBtp">pic.twitter.com/nVEAfywBtp</a> —@1Racer78

"We're still waiting to find out exactly what it was," he said.

Officers wearing protective gear and masks could also be seen at the scene.

A second package is still being examined.

Moreton didn't say how long roads in the area would be closed for the investigation.

Fire department public information officer Claudio Mostacci confirmed that the fire department was also on scene at the request of police.

He said firefighters were standing by, and couldn't comment on the nature of the investigation.