Fourth blast rocks New Zealand death mine

Another explosion on Sunday tore through a New Zealand colliery where 29 miners died earlier this month, police said, adding no one was injured in the latest blast.

The blast, the fourth at the Pike River coal mine since an initial November 19 explosion trapped the men, occurred just before 2:00pm (0100GMT) and demonstrated the colliery's volatility, police said.

"There were no injuries and people working near the entrance to the mine were moved away from the area for their safety," superintendent Dave Cliff said.

Emergency crews have been unable to recover bodies from the remote South Island mine because it remains flooded with explosive methane gas.