Ten people were killed and many others injured in four booby-trapped cars' explosions in the Iraqi capital, Baghdad, on Saturday, police said.The most powerful explosion took place in Al-Ameen neighborhood, eastern Baghdad, killing four persons and wounding 14 others, the source told KUNA.The three other blasts, which occurred in Cairo and Al-Amel neighborhoods, and Al-Sadr City, killed six people and injured 22 others, added the source. No one claimed responsibility for the attacks.