Brendan Cox, the husband of slain British lawmaker Jo Cox, said those who carried out an attack outside of U.K.’s Parliament on Wednesday “will not succeed in dividing us.”

Whoever has attacked our parliament for whatever motive will not succeed in dividing us. All of my thoughts with those injured. — Brendan Cox (@MrBrendanCox) March 22, 2017

Shots were fired and a man was seen wielding a large knife outside Parliament just before 3 p.m. local time Wednesday. At least four people were killed in the attack, along with the assailant, and 40 were injured.

Cox was a lawmaker for the opposition Labour Party when she was shot and killed in June 2016 ahead of an event with constituents. After her death, her husband called on people to fight back against “hatred.”

“She would have wanted two things above all else to happen now: one, that our precious children are bathed in love and two, that we all unite to fight against the hatred that killed her,” he said.

Read more on the attack at U.K. Parliament here.