BERLIN -- Two music researchers have discovered in Berlin a previously unknown opera by the 18th-century German composer Georg Philipp Telemann, one of them told reporters Friday.

Researcher Peter Huth said he and his colleague Raschid-Sascha Pegah had found the opera while going through archives at the Berlin Singing School, AFP reported.

The two-hour work, "Pastorelle", is the oldest drama by the composer to have been discovered. The Libretto -- partially in French, partially in German -- was apparently composed between 1705 and 1710, Huth said.

Telemann was born in the eastern city of Magdeburg in 1681 and died in Hamburg in the north in 1767.

The archives were seized during World War II by the Soviet army and were returned to Germany by Ukraine after the fall of the Berlin Wall in 1989.