WEST MELBOURNE, Fla. -- West Melbourne police said Central Middle School officials refused to fully cooperate with an evacuation on Tuesday morning after a sixth bomb threat was made this school year.

But school district officials said they investigated the threat, found it unwarranted and let students and teachers back into the school.

"I think this comes down to an issue of colliding procedures," Brevard School District Area Superintendent Tom McIntyre told Local 6 News partner Florida Today.

West Melbourne Police went to the school at about 10:30 a.m. after a hand-written note was found in a boy's restroom near the gymnasium. School officials had evacuated the students but began to allow them to return before the police could search the school with bomb-sniffing dogs, police spokesman Steve Wilkinson said.

Wilkinson said the students were out for 15 minutes, but district officials said they waited outside for an hour while school officials conducted their own investigation and search.

"Central Middle School students were indeed evacuated earlier today for approximately one hour due to a possible threat," said Wes Sumner, school spokesman. "During the course of the evacuation, school officials located a witness who has provided information on possible suspects. School officials proceeded to search the school and area. Once secured, students were allowed to return and classes resumed."

Police backed off but not without protest.

"This decision is against my better judgment," West Melbourne police Chief Brian Lock said. "Until you can show me with 100 percent certainty that it is a hoax, I believe we should evacuate and ensure the safety of the students and faculty."

Lock pulled his school resource officer out of the school, saying he will not risk his officer's safety.

In addition to Tuesday's threat, Central Middle School has had bomb threats made against it on Sept. 24, Sept. 26, Oct. 4, Oct. 9 and Oct. 12. Four students have been arrested in the previous threats on charges of disruption of an educational institution and false report of a deadly explosive.

A Central Florida teen was arrested last week in Clermont after he allegedly made a threat against his school. Police said they found a bomb in the teen's home that he threatened to use at his school.

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