MIAMI -- A bomb squad investigated a report of a suspicious package after police evacuated four of six concourses at Miami International Airport for several hours on the eve of the Labor Day travel period, an airport spokesman said Friday.

Police bomb squad authorities went about 9:30 p.m. Thursday to a Customs area of Concourse E near an international arrivals area when the initial report came in, airport spokesman Greg Chin told The Associated Press.

He said between 100 to 200 passengers were evacuated while police investigated and that flights overnight were allowed to use parts of two concourses still open.

Chin declined to elaborate on the nature of the suspicious item and referred all calls to the Miami-Dade police. Police did not immediately return repeated telephone calls for comment.

"I'm still not sure how many flights came in during this time, but any that did were relocated to the eastern or western ends of the airport," Chin said early Friday.

He said parts of Concourse D and J remain open to flights, but all four of the middle concourses in the 2-mile-long airport complex remained closed to the public for hours.

"We're just waiting hopefully for an all clear," Chin said.

He said most of the passengers still in the concourses were initially taken outside.

"We had to have passengers moved out on the curbside," he said, adding most of those returning to the build were allowed into the areas of the two concourses still open.