Human Rights Watch has urged Kiev to stop using unguided Grad rockets which it said have killed at least 16 civilians in four recent attacks, warning that firing such weapons at populated areas could amount to war crimes.



The rights group yesterday said that both government forces and pro-Russian rebels have used Grads -- unguided rockets fired in salvos and sprayed across a wide area -- as they battle each other in eastern Ukraine.



Although Kiev has denied using the Soviet-designed systems around major cities, HRW said investigations into four attacks between July 12 and 21 in the insurgent-held industrial hub of Donetsk "strongly indicates that Ukrainian government forces were responsible for" firing the Grads.



It also accused insurgent forces of having recently used such rockets, but did not give details.



"Grad rockets are notoriously imprecise weapons that shouldn't be used in populated areas," said Ole Solvang, senior emergencies researcher at Human Rights Watch.



"If insurgent and Ukrainian government forces are serious about limiting harm to civilians, they should both immediately stop using these weapons in populated areas."



HRW's claims came after the Red Cross declared that Ukraine is in a civil war -- an official distinction that would allow warring parties to be prosecuted for war crimes.



"Ukrainian authorities should order all its forces, including volunteer forces, to immediately stop using Grads in or near populated areas," Solvang said.



"Commanding officers on all sides should recognise that one day they could face legal consequences for their actions."



Among the four July attacks was one close to the Donetsk train station, when a residential area nearby was hit by the rockets, killing three.



Two separate strikes on July 12 killed at least 13 civilians around rebel stronghold Donetsk, a city with a population of about one million.



HRW also blamed insurgents for moving closer to the centre of town in one incident when their base was hit, saying: "Violations of the laws of war by one side to the conflict do not justify violations by the other side.