Police have charged Aidan Kay, a priest at St Mary's Catholic Parish in Wellington, with an offence following a complaint, the Catholic Archbishop of Wellington John Dew said in a statement yesterday.

Father Kay was based in Hobart for five years and took up his post in New Zealand in February 2013.

"As this case is due before the courts no further details will be discussed," Archbishop Dew said.

Archdiocese vicar-general Monsignor Gerry Burns told parishioners at mass yesterday that police had charged Father Kay, a Passionist priest, with indecent assault following a complaint, The Marlborough Express reported.

The announcement was greeted by gasps and exclamations of horror.

Parishioners were shocked by the news, and some at the vigil Mass were in tears.

"The police are handling it from here. It is before the courts."

Monsignor Burns would not discuss what the charge was.

A police spokeswoman confirmed a 71-year-old Blenheim man would appear in court tomorrow for his first appearance on one charge of indecent assault on a male aged over 16 years of age.

Monsignor Burns said the matter was "very serious" and both the archdiocese and the Passionist order were "fully co-operating" with police.

Father Kay would not be returning to the parish, he said.

Passionist provincial superior Father Tom McDonough, who flew from Australia after the police alerted the church to the charge, said he was very sad this was the occasion that had brought him to Blenheim.

Fr Kay was born in New Zealand.