Democracy will not be thwarted by terrorism, Arlene Foster has said in the wake of the London attack.

The leaders of Northern Ireland's main parties will restart their election campaigns today after suspending them yesterday for the day as a mark of respect to the victims.

Joining other political leaders in their expression of sympathy for the families of those killed, DUP leader Mrs Foster said: "Northern Ireland stands with the people of London."

The former First Minister offered prayers for those who had been bereaved and injured, saying the people of London had been challenged once again by evil.

"Terrorism depends upon fear and is the enemy of democracy," Mrs Foster said.

"The United Kingdom is one of the greatest democracies and our Parliament is a beacon of hope around the world.

"Our democracy will not be thwarted or derailed by terrorism."

She praised the security services, police and emergency services for their swift response and bravery.

Ulster Unionist leader Robin Swann said: "These were the wicked actions of terrorist thugs who cowardly targeted innocent people enjoying a night out.

"It is a shocking manifestation of the hatred our enemies have for our way of life and the free and democratic society which we hold dear.

"No matter what the terrorists do, they will not win.

"We must be thankful for the heroic actions of the men and women of the Metropolitan Police and emergency services who ran towards danger to deal with the aftermath and bring this situation to a rapid end, and also the members of the public who fought the terrorists off.

"But for their bravery, this could have been a lot worse than it already is.

"Northern Ireland will stand with the people of London. They have endured terrorism like this before, but their spirit will not be broken.

"London and its people are resilient and will stay strong."

Alliance leader Naomi Long has said people must remain strong following the attacks.

"My foremost thoughts and prayers go to the loved ones of those killed in London, as well as anyone else caught up in this horrific attack," she said.

"My thanks also go to the emergency services, who proved once again they operate without fear or favour in dealing with the incident and its aftermath.

"It is difficult to comprehend the mindset of those who would carry out this terror against people simply out enjoying their weekend.

"Despite last night's incident and the recent attack in Manchester, we must remain strong and continue to live our lives without fear or trepidation.

"By doing so, these terrorists can never win.

"London was my second home for five years - it is hugely cosmopolitan, yet made up of many bustling, friendly neighbourhood communities.

"Despite this horror, I know it will not lose that uniquely London aspect to its character."

PSNI Chief Constable George Hamilton also extended his condolences to the victims.

"My thoughts and sympathies are with the people of London following this horrendous attack.

"We also send our support to our colleagues in the Metropolitan Police, City of London Police, British Transport Police and all the emergency services that responded last night."

The "horrendous attacks" were condemned by Sinn Fein leader Gerry Adams.

"On behalf of Sinn Fein, I offer my sincere condolences to the victims and the families of those killed and injured and to the people of London," he said.

The party's leader in Northern Ireland, Michelle O'Neill, also condemned the attacks.

She said Sinn Fein cancelled all election activity yesterday "apart from local canvassing" as a mark of respect to those killed and injured.

Belfast Telegraph