PHUKET Prison is full to bursting as the island's administrators attempt to resolve a procedural glitch to ensure cases can be pursued against the rising number of alleged drug abusers on Phuket.

More than 500 people have been arrested for drug offences so far this month, topping the 470 recorded in July, Phuket Governor Wichai Praisa-ngob was told at a meeting at Provincial Hall in Phuket City today.

Phuket Prison, built for 750 inmates, now has 1268 occupants of whom 54.18 percent had been found guilty or were awaiting trial for drug offences, the governor heard.

Non-Thai inmates included 38 from China or Taiwan, 29 Burmese, three Britons, three French, two Afghanis, two Bangladeshis, two Cameroon citizens, two Malaysians, two Singaporeans, and single citizens from Germany, Cambodia, Sweden, Tunisia, Pakistan, India, Italy and the US.

A change in the law now requires a doctor to verify drug test samples, and the governor today asked Public Health to quickly establish a verification centre on Phuket. Sending samples to Surat Thani had proven to be an ineffective method because the delay made confirmation testing of positive samples unreliable.

The governor rejected as too expensive an option to purchase a drugs scanner that could ''see'' through metal for a cost of 250 million baht, plus one million baht monthly maintenance. The detector has only been employed so far on major national border crossings.

Of the 1268 inmates in Phuket Prison, 1101 are male and 167 female, with another 76 males and 10 females being treated at the island's drug adiction centre. So far this month, seven males and two females have either completed jail terms or been freed on bail pending trial.

Random drug testing of 100 patrons at 26 bars after the governor strolled through Soi Bangla in Patong at midnight on Friday produced no positive findings. However, three bars in Patong and one in Phuket City have been closed this month for violating the terms of operating permits.