Police have appealed for more victims to come forward after a 52-year-old man in California was arrested following an admission that he sexually abused numerous children since the early 1980s.

Caleb Hesse, of Joshua Tree, California, admitted the inappropriate contact between him and various minors. He was charged with four lewd acts with a child.

Investigators believe that the incidents took place throughout his career as a teacher in Morongo Unified School District, where he worked since 1987, and most recently as an elementary school teacher.

Hesse, an active long-term volunteer for the Evangelical Free Church of Yucca Valley, has been detained, and booked at Morongo Basin Jail, with bail set at $2.5million, KESQ.com reported.

The Evangelical church, which is known for being extremely anti-gay, has hosted overnight camping trips, at which police believe many of the incidents took place.

Investigators believe that many of the children he abused will now be between 30 and 40 years old and have made an appeal for anyone with information to come forward. They also believe that the incidents may have taken place as recently as 15 August.

Caleb Hesse was a well-known anti-gay activist, and had donated to Propostion 8, the voter-approved ban on gay marriages in the US state of California.

Hesse was detained on August 17, but changed his plea to “not guilty” at his arraignment on August 21, and recanted his confession.