Home Secretary Theresa May told the Conservative Party conference: "We should not for one second underestimate the threat we face from terrorism and the challenges we must meet in confronting extremism."
"Whatever the race, religion and beliefs of a terrorist, whatever the race, religion and beliefs of their victims, this is Britain.
"We are all British. We stand united against terrorism and we will never succumb to violence."
More top news
The High Court will hear a legal challenge to Labour's decision to guarantee Jeremy Corbyn a place on the party's leadership ballot.
Russian Foreign Minister Sergei Lavrov brushed aside accusations that Moscow was behind the hacking of internal Democratic Party memos.
The First Lady gave an enthusiastic backing for the Democratic presidential frontrunner in a speech at the Democratic National Convention.