An undercover drug investigation prompted Warren school officials to take some special precautions as classes began at the Jefferson PK-8 building Thursday morning.

The school told 21 News that there was police activity at around 8:30 am in the part of the area where students walk to Jefferson.

Bus drivers were told to pick up the students as usual, but be prepared to not drop them off at school.

School officials say the situation was resolved before the start of classes, and school began as usual.

Tony Villanueva of the TAG Task Force told 21 News that they were conducting an investigation with the DEA Thursday morning along with Warren police and the FBI. 

There is no word on whether any arrests have been made.