Fourty-four Nobel Prize laureates in various disciplines have signed a letter expressing concern over what they call deteriorating conditions for democracy and human rights in Guatemala.

The letter released Thursday urges Guatemalan authorities to safeguard peace and democracy.

Among the signatories is Guatemalan indigenous rights activist Rigoberta Menchú, who won the Peace Prize in 1992.

Jody Williams (Peace Prize, 1997) said progress to combat corruption and impunity for abuses dating to the country's civil war has suffered a reversal and needs support from the international community.

Others who signed the letter won in areas such as literature, medicine, economics, physics and chemistry.