MADISON, Wis. -- The sirens that sounded across Dane County Thursday were part of a state tornado drill, and all but four of them went off.

Dane County emergency officials knew three of the four sirens that didn't go off were down for repair or relocation.

The sirens that are down for repair are at Bridge Road in Monona, East Dean Avenue off Monona Drive in Madison and in Cottage Grove.

But officials said they don't know why a city-owned siren at Sycamore Road on the East Side failed to sound.

"The point of the test is not to prove that they all work. The point of the test is to find out which ones don't. And so, yes, having a good result is a good thing but we run these tests to find out where the problems are," said Dave Janda, of Dane County Emergency Management.

Last year in April, half a dozen county sirens did not sound.

Officials said those that were silent Thursday should all be working within a week. They also said other severe weather warnings, like reverse 911 notification for the deaf and e-mail alerts for those who've signed up for it, also worked well.

Residents in Madison's Triangle neighborhood, near the University of Wisconsin-Madison campus on Thursday conducted a full-scale tornado drill at the Brittingham Apartments.

Fire officials helped with notification due to the number of disabled and non-English speaking residents in the neighborhood.