An anonymous bomb threat called in to Grosse Pointe South High School Thursday afternoon is under investigation. Grosse Pointe Farms, City of Grosse Pointe and Michigan State Police were on the scene for about three hours. 

The state's bomb squad robot was employed to check the area believed to be suspicious, discovering a box of fireworks, but not a bomb, Farms Public Safety Director Dan Jensen said. 

The call came in to a secretary at the school about 3:30 p.m. Thursday and the secretary followed protocol. She questioned the adult male caller for several minutes, which aided police, and she took down the phone number from where the call was being made, Superintendent C. Suzanne Klein said. 

A handful of employees were in the building, which was evacuated, but no students were on the campus as summer school is not located at South this year, Klein said. 

The caller provided the secretary with many details, including that the bomb was placed near the "quad area," could be near a park bench or in a garbage can. When the secretary questioned the man about it being summer, he said he'd driven by and saw kids on the grounds, Jensen said.

Jensen said the details along with the circumstances caused officials concern. Officers found a T-shirt that had burn marks on it from being lit on fire. It was on top of a box—later discovered to be filled with bottles of Gatorade—on top of a garbage can near a park bench in the area of the the athletic fields—what some might consider the quad, Jensen said.

Years ago there was an area near the arched gates that former Grosse Pointe South students referred to as the quad, and it was the area where students were allowed to smoke, Jensen said.

Initially, Michigan State Police responded with a bomb sniffing dog but called the dog off after officials decided to deploy the bomb-disarming robot, Jensen said. 

Fisher Road was blocked off by police for nearly three hours, but pedestrians also were allowed to walk along the sidewalk on the opposite side of the street. When Klein arrived on the scene, she escorted an officer to the former quad area to check that nothing out of the ordinary was there. 

The robot found a box of fireworks in the garbage can and within several minutes the street was reopened to traffic and crews left the scene. The Grosse Pointe Farms fire department was on the scene for the entire time dressed in full gear should response be necessary. 

This is the first bomb threat the district has had in several years, and the first Klein recalls ever being in the summer when students are not present, she said. 

Jensen said that during the investigation they discovered the call came from a call center that they later found out is known for making "bogus" calls.

It is unknown whether the threat had anything to do with the heightened political environment surrounding South High School, Jensen said. 

The school has had a variety staff turnover and controversy in the last several months, including the unexpected sudden resignations of the principal and assistant principal in connection with a still ongoing investigation into inappropriate images being shared on school computers and Blackberries.

A teacher will also be going before the Michigan Tenure Commission to fight to keep her teaching certificate after being sentenced in Ohio on five felony charges stemming from the long-term theft of money from her mother's business.