Athens - Greece is detaining hundreds of illegal immigrants in cramped an squalid conditions at a reception center on the Mediterranean island of Lesvos, the French charity Medecins Sans Frontieres (MSF) charged Wednesday.

Some 800 immigrants, many of them from war-torn Afghanistan, are living in overcrowded rooms in the detention center without proper sanitation and medical care, according to the agency. Some are suffering from serious diseases.

"They do not have adequate access to showers and toilets," MSF local project leader Giorgos Karayiannis was quoted by the Greek daily Kathimerini as saying.

According to Karayiannis, the immigrants are only allowed outside for half an hour every couple of days and one ward offers only one toilet for more than 100 people.

"They are usually kept locked up," he said.

Some of the immigrants are suffering from tuberculosis and skin diseases and have to wait to be seen by the one on-site doctor, according to Karayiannis, adding that there is not enough staff to meet the centre's demands.

He said MSF had been working at the centre for two months providing medical assistance and had seen a rise in the numbers of migrants from about 150 in June to about 800 at present.

Last week another French charity, Medecins du Monde, accused Greece of neglecting 140 war refugees who had been evicted from their reception centre on the Aegean island of Patmos.

Every year thousands of would-be immigrants attempt to make their way into European Union Greece, mainly from Africa, the Middle East and neighbouring Turkey.

In 2006, more than 10,000 immigrants took advantage of Greece's 15,000 kilometre, poorly-patrolled Mediterranean coastline and arrived in boats.

Greece has only six detention centres for illegal immigrants and says it does not have sufficient resources to handle the influx.

On entering the country, immigrants are detained at the centres for up to three months before being given one month to leave the country.

Some find their way to Greece's major cities, while the majority end up reaching wealthier European countries like Italy.

EU ministers backed French proposals for a common policy to stem illegal immigration in the 27-nation bloc which is expected to be adopted in October. (dpa)