Police in southern India are investigating a suspected attempt to illegally transport scores of Indians on an overcrowded boat to New Zealand.

The additional superintendent of police in Kerala state said police were questioning people who failed to board the fishing boat, who said it left nine days ago for New Zealand.

Sojan, who uses one name, said police began investigating when they found dozens of abandoned bags containing dried fruit and “everything needed for a sea journey” near the harbour in Kochi in Kerala state.

“The boat is gone, that's for sure,” he said by telephone on Monday.

Police believe the fishing boat was so overcrowded that people had to leave their luggage behind. Sojan said it was unclear where the boat might be.

“We have not been able to trace the boat so far, no radio connection, no radar, nothing is coming out,” Sojan said. “It was a fishing boat, not a passenger boat. The boat had been purchased just for this purpose.”

He said no arrests had been made.

The Indian Express newspaper said police recovered more than 50 abandoned bags near Kodungallur temple in Thrissur district and later found more bags at Munambam harbor in Kochi.

The newspaper said the bags containing clothes, IDs and other documents belonged to about 230 people. Sojan said it was unclear how many might be on board, but "more than 100".

There has never been a large boat arrival of asylum seekers in New Zealand, due in part to country's isolation in the South Pacific and the often treacherous ocean conditions. But the country is seen as more welcoming than neighbouring Australia, which refuses to resettle asylum seekers arriving by boat in a policy intended to deter such journeys.

“Although there has never been a mass arrival in this country, there's no doubt that New Zealand is a target for people smugglers and a mass arrival at some stage is a very real possibility that we need to be fully prepared for,” said Stephen Vaughan, an assistant general manager at Immigration New Zealand, in a statement.

Vaughan said the agency did not comment on specific cases but it remained vigilant.

“The message to anyone contemplating such a journey is simple: Any attempt to reach New Zealand will put your life, and the lives of your family members, at great risk,” he said. “There is every chance you will drown at sea.”

New Zealand law allows for large numbers of asylum seekers arriving by boat to be detained for up to six months while authorities assess whether they pose a security risk.