A convicted pastor is back on trial in Germany after he appealed his prison sentence for sexually assaulting his underaged assistants.

Former parish priest Peter Wagner of Pfaffenhofen an der Ilm, Bavaria, was given four months in jail for sexually assaulting minors, including an altar boy at his church.

But the clergyman appealed the decision, and the case was brought again before the Pfaffenhofen District Court, on 6th March.

The 56-year-old was first targeted by investigators after one of his former altar boys approached another pastor and told him about Wagner’s sick acts.

He was charged when evidence led cops to the pastor’s home, where they found porn videos showing young men.

Another of his victims then turned to the police after 13 years of keeping quiet, and told them that Wagner had first sexually abused him 2005.

The victim, now aged 30 but a teenager at the time of the abuse, told the court he had remained silent out of shame.

Testifying under witness protection, he said: “I had feelings of guilt and fear.”

He explained that he considered Wagner a father figure, and that the priest had even baptised him and gone shopping with him in Munich.

But he added: “When I told him I was going to the gym, he wanted to measure my muscle gain.

“For this I was asked to undress down to my underpants.

“Every one to two months he measured my arms, legs and chest with a tape measure.”

Prosecutor Alexandra Engel explained: “So that he could see how strong the injured party was, he had to lie down on a couch.

“[The victim was] wearing only his underwear, his wrists were tied and he was asked to free himself.”

Wagner then reportedly locked him in shackles and rubbed his genitals for five minutes.

He also made him watch porn, the victim alleged.

Wagner was reportedly dismissed from Pfaffenhofen Parish after more allegations of him abusing minors emerged in 2016.

Reports revealed that about 50 altar boys resigned from service during his time at the church.

But he soon got a new pastorate in Elchingen, Neu-Ulm District, after no incriminating evidence was collected.

The final verdict is expected on 13th March.

Wagner has been suspended from his duties pending the outcome.