At least 49 people were killed and 20 wounded in two shootings in mosques in the city of Christchurch in New Zealand on Friday morning (local time), according to local media.

The local police commissioner confirmed that there were multiple fatalities in the shootings. One person is in custody.

Police called on residents of central Christchurch to stay indoors.

"A serious and evolving situation is occurring in Christchurch with an active shooter," police said in a statement.

"Police are responding with its full capability to manage the situation, but the risk environment remains extremely high."

An eyewitness, Len Peneha, was quoted by The Associated Press as saying he saw a man dressed in black enter the Masjid Al Noor mosque and then heard dozens of shots, followed by people running from the mosque in terror.

He said he also saw the gunman flee before emergency services arrived.

Radio New Zealand quoted a witness inside the mosque saying he heard shots fired and at least four people were lying on the ground and “there was blood everywhere”.