Three were killed and dozens were injured when two bombs went off on Monday near the finish line of the Boston Marathon.
Warren said that Boston residents would not let this “cowardly and despicable attack” affect them.
“We will not be afraid and we will not let it change us,” Warren said. “Bostonians are tough, we are fighter and we will not be broken.”
Sen. William Cowan (D-Mass.) praised the first-responders and volunteers for their help during the attack. He also said law enforcement will find the attacker.
"Make no mistake, we will find them and justice will be done," Cowan said.