A St. John's radio station's wildly popular contest proved powerful enough to knock out emergency phone lines on Thursday.

HITS-FM gave away $10,000 to a caller on Thursday, wrapping up a heavily publicized contest.

But the volume of calls between 11 a.m. and 11:20 was so intense that the St. John's Regional Fire Department was unable to make outgoing calls, and 911 calls were switched over to a cellphone-based backup system.

Many customers — including some emergency service providers — temporarily lost dial tone.

BellAliant said it has never seen so many calls in such a narrow time frame in the St. John's area.

Company official Mark Duggan said calls were up by as much 600 per cent, tying up lines far worse than during its busiest period, Mother's Day.

"We've certainly been in touch with the radio stations to raise our concerns, and we'll be in touch with others to see, are there different ways to run contests that don't put that kind of pressure on the network?" Duggan said.

Duggan said businesses were especially hard hit by the contest, as employees tied up lines phoning the radio station.