The Aksa Martyr's Brigades in the Gaza Strip announced that it has developed a new rocket called 'Yasser 1' capable of reaching the Israeli city of Ashkelon, Army Radio reported Sunday. The group described the new rocket as an improved version of the Kassam with a record firing range of 15 km. IDF officials in the past expressed concerns that terror organizations, including Hamas are seeking to upgrade their Kassam rockets.