In December, U.S. and NATO officials confirmed rebel reports that Syrian forces had fired Scud missiles at rebel areas in the north. That was the last confirmed use of such weapons.
Also Tuesday, rebels clashed with government forces near Aleppo’s international airport and the Kweiras military airport nearby, the Observatory said. Clashes have halted air traffic to the two airports for weeks, since rebels launched their offensive to try to capture them.
The Observatory also reported government shelling, airstrikes and clashes between government forces and rebels east and south of Damascus.
Seven people were killed in rocket strikes on the eastern suburb of Kafar Batna and five died in a car bombing in Jdeidat al-Fadel, southwest of the capital, it said.
The U.N. says some 70,000 have been killed since the uprising against Assad’s authoritarian rule began in March 2011. The violence has spread humanitarian suffering across much of Syria.
U.N. humanitarian chief Valerie Amos said the number of people in need of humanitarian assistance has quadrupled since June last year.
‘‘Just in the last two months, over 250,000 people have fled into neighboring countries. These numbers, they are not sustainable,’’ she said at a press conference in Geneva.
The U.N. says more than 870,000 Syrians have fled to neighboring countries since the beginning of the conflict, with the majority seeking refuge in Jordan, Turkey and Lebanon.
The United States announced Tuesday it was providing an addition $19 million in humanitarian assistance in response to urgent needs in Syria.
The announcement made in Geneva by Nancy Lindborg, assistant administrator for the U.S. Agency for International Development, brings the United States’ total contribution of humanitarian support in response to this crisis to nearly $385 million.
On January 29, President Barack Obama announced an additional $155 million to help those suffering inside Syria and refugees in the neighboring countries.
The U.N. warned in a report released Monday that contaminated water and poor hygiene in populated areas have led to an increase in waterborne diseases such as Hepatitis A and Typhoid.
The World Health Organization said the health situation on the ground is rapidly deteriorating, with an estimated 2,500 people in the northeastern Deir el-Zour province infected with Typhoid and 14,000 cases of Leishmania, a parasite responsible for an infectious and often debilitating disease, in Hassakeh province.
Associated Press writers Albert Aji in Damascus, Bassem Mroue and Ben Hubbard in Beirut, Frank Jordan in Berlin and Nataliya Vasilyeva in Moscow contributed reporting.