PRAGUE (Reuters) - Eight people have died in the Czech Republic after drinking bootleg vodka and rum containing methanol, police and media said on Tuesday, in the worst case of fatal alcohol poisoning in the country in at least 30 years.

Around 20 people remain in hospital and police warned more cases could emerge.

While such serious cases are rare in the central European state of 10.5 million, state and industry officials estimate that illegal alcohol sales are up and account for 10-20 percent of the market.

The first victim was taken into hospital last Thursday in the Moravian-Silesian region in the northeast of the country, 350 km (217 miles) east of Prague.

Stepanka Zatloukalova, a police spokeswoman, told Reuters seven people had died, while the Czech news agency CTK reported an eighth fatality in the Zlin region. A police spokesman for the region could not be reached.

Police have detained a 36-year-old man suspected of being the source of the tainted alcohol.

Prime Minister Petr Necas called the situation serious. The Health Ministry has stepped up checks on restaurants and bars after some of the suspect alcohol turned up in Prague.

(Reporting by Jana Mlcochova and Jason Hovet; Editing by Andrew Osborn)