A boat carrying Indonesians sank off Malaysia’s west coast on Tuesday, killing one girl and leaving at least 14 other people missing.

Authorities rescued seven other people, five men and two women, said Baljeet Singh, a district police chief in southern Negeri Sembilan state. He said the girl who drowned is believed to be 7 or 8 years old.

Mr. Singh said four vessels and an aircraft would continue searching until sunset for those missing.

He said heavy rain, rough seas and overloading may have caused the fishing boat to sink.

Police were investigating whether the passengers were illegal migrants as none of those rescued had valid documents, he said.

Rizal Ramli, the state’s marine police chief, had said earlier the boat had come from Indonesia. But Mr. Singh said those rescued had said the boat was headed to Indonesia.

Dozens of migrants have died in boat accidents in recent years while travelling between peninsular Malaysia and Indonesia’s Sumatra island, which are separated by the Malacca Strait, with a reputation for rough seas. Most of the boats are overcrowded and rickety.

The Indonesian Embassy estimates some 800,000 Indonesians live in relatively wealthier Malaysia without valid immigration documents. Many are employed in plantations, construction sites and restaurants.

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