A suspect died after spending four days in police custody in Langkawi, Kedah.

In a statement, Bukit Aman's Integrity and Compliance Department director Azri Ahmad said the 34-year-old woman was arrested on Dec 12 and was hospitalised yesterday.

She was declared dead at 7.30am today. An autopsy will be performed tomorrow at the Sultanah Bahiyah Hospital in Alor Setar.

Azri said the cause of death is being investigated.

The suspect was arrested under Section 15(1)(a) and Section 39B of the Dangerous Drugs Act 1952.

The recently amended Section 39B criminalises drug trafficking by punishment of death at the discretion of the judge. It also carries a penalty of whipping of not less than 12 strokes. Section 15(1)(a) relates to self-administration of illicit drugs.

Bukit Aman's Integrity and Compliance Department was set up in 2014 and has been regularly publicising incidents of deaths in custody.