BELFAST, NORTHERN IRELAND (AP) -- Northern Ireland's major maternity hospital has evacuated its unit for premature babies after three died from a bacterial infection.

A doctor at the Royal Maternity Hospital in Belfast, Clifford Mayes, says the 13 babies remaining in the neonatal unit are being moved to isolation rooms while the unit is extensively cleaned and an investigation launched.

Mayes said Friday that the first baby died Jan. 6, the second Jan. 13 and the third Thursday night. He said the Pseudomonas bacterium responsible is not particularly contagious and poses little threat to healthy humans, but proved lethal to ill and premature babies.

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