FERNDALE, WA (MyBellinghamNow.com) – Students at Ferndale High School are in secure protocol a day after they were evacuated.

The district said in a statement to parents that an outside threat was being investigated on Friday, Oct. 4.

In secure mode, classes continue as usual, but no one is allowed to leave or enter the building. A later update stated that the campus would remain on secure mode through the rest of the day.

It comes a day after the high school was evacuated due to a bomb threat that was found to be not credible.