Image copyright Police handout Image caption Police say they have got to the bottom of the "mystery pooper" investigation

Police hunting a suspect who relieved himself on school grounds "on a daily basis" in the US state of New Jersey have arrested a top education official.

Kenilworth school superintendent Thomas Tramaglini, 42, was detained after investigators set up a sting operation to snare the "mystery pooper".

Police were called after students complained of frequent excrement near their school running track and field.

Mr Tramaglini is charged with lewdness, littering and defecating in public.

In a statement, the Holmdel Township Police Department said they opened an investigation after high school staff and sports coaches reported "they were finding human faeces, on or near the area of the High School track / football field on a daily basis".

According to local media, the superintendent lives about three miles (4.8km) from the Holmdel High School in Monmouth County, 40 miles from New York City.

On Monday at 05:50 local time (09:50 GMT), officers approached the superintendent while he was running at the school track, the scene of the alleged crime.

Image copyright Google Maps

Mr Tramaglini, who earns nearly $150,000 (£110,000) per year as head of the local education authority, was arrested.

Police officers said they had just observed him in the act.

Vito Gagliardi, a lawyer for the school board, told APP.com that Mr Tramaglini has been "highly regarded" during his three years as head of the local schools.

The superintendent has been placed on paid leave, according to the Kenilworth Public School district.

"Given the nature of those charges, he asked for and was granted a paid leave of absence," the school board wrote on Facebook.

"Leaves can only be without pay in the face of indictments or tenure charges, as a matter of state law."

It is unclear why Mr Tramaglini allegedly did not use toilet facilities.

On Facebook, local residents speculated on his potential motive, with some arguing he should not be punished unless his intent was malicious.

Others questioned whether Mr Tramaglini, if guilty, could have a condition that left him unable to restrain his bowel movements.

Social media jokesters have dubbed the culprit "the super pooper" or the "poopetrator".