THE HAGUE - THREE Dutch citizens were among those injured when bombs exploded in two luxury hotels in Jakarta on Friday, killing at least nine people, the foreign ministry said in The Hague.

'I can confirm that three Dutch citizens were injured, two of them seriously,' a ministry spokesman said.

Further information was not immediately available.

Meanwhile, New Zealand Prime Minister John Key has confirmed that a New Zealander is among at least nine people killed when bombs exploded in two luxury hotels in central Jakarta on Friday.

The man, whose name was not immediately released, was said to have been at the Marriott Hotel for a business meeting.

'While we are still receiving information from the embassy (in Jakarta) about what happened, I would like to convey my deepest sympathy to the family and friends of the New Zealander killed,' Mr Key said.

At least two Australians were among some 40 people wounded, said Australian foreign affairs department, which described the blasts as 'barbaric attacks.'

'It appears these attacks were coordinated and premeditated,' a spokesman told AFP, adding that the department 'unreservedly condemned' the violence.

She said consular staff were urgently seeking to locate the injured Australians to confirm their welfare, and were also seeking to establish whether any other Australians had been injured.

'The government has never lost sight of the threat from terrorism in the region,' she added.

A man who identified himself as Jim earlier told commercial radio his son had phoned him from the Indonesian capital to say his leg was wounded and he had lost hearing in one ear in the explosion at the JW Marriott hotel.

His son was on his way to hospital, but apart from his leg injury, was otherwise okay, he said.

'He was in the explosion and he was bleeding from the left leg, although from what I can gather the injury is not serious,' he told the Fairfax radio network.

'He lost his hearing in one ear, but he thinks he will recover from that, and he's on his way to hospital. He's okay,' he added. -- AFP