CHICAGO (CBS) — Reports of smoke in the Belmont Blue Line subway station sent several firefighters and ambulances to the Northwest Side, but turned out to be unfounded.

Smoke was reported in the tunnel at 3355 W. Belmont, but nothing was found, according to Fire Media Affairs spokesman Quention Curtis, who said an EMS Plan 1 and still and box alarm were immediately canceled.

However, emergency crews had shut down power to tracks in both directions between Sacramento and Irving Park for a short time. Blue Line trains were running again Friday afternoon, with only minor delays, according to an alert posted on the CTA’s website.