Two explosions have hit Syria's northern city of Aleppo, state-run TV said on Friday. The attack struck the security compounds, killing at least 28 people and wounding 175 The blasts were the first in Syria's largest city. It has not been affected seriously by the Syrian uprising that began in March. Colonel Arif Hamood of the Free Syrian Army claimed responsibility for the two blasts that targeted military and security buildings in the city.