Toronto police have busted a suspected drug lab in the city's north end.

They raided a duplex on Woburn Avenue, near Avenue Road and Lawrence Avenue West, overnight Tuesday to Wednesday.

The discovery was made in the middle of the night after neighbours reported a suspicious odour.

Firefighters were called, and they then called police.

"As a precaution, [police] closed Woburn Avenue, east- and westbound, from Avenue Road to Gray Road," Staff Sgt. Mike McKeown said.

Teams trained in dealing with hazardous materials, as well as several fire vehicles, were there throughout the day.

Police later confirmed they had found evidence to suggest the home was outfitted to produce crystal meth.

There was no one in the home when police arrived. So far there have been no arrests.