Commenting on the attack in Westminster, Liberal Democrat leader Tim Farron said:
"These were horrific and deeply tragic events and my thoughts and prayers are with the family and loved ones of those who lost their lives today and the many more who are injured.
"The bravery and professionalism of the police and emergency services has been truly humbling."
"When the attacks happened, many people, both police and civilians, ran towards the danger in order to help. Their bravery was awe-inspiring."
"Our response is to this must be more democracy, more openness, and more humanity. We will answer hatred with love."
"At times like this, we must remember who we are. Britain is an open, tolerant country and we will never let those who spread terror and threaten our values win."