Scotland's papers: Brexit begins and firebomb attack
Almost all of Thursday's front pages report on the delivery of the Article 50 letter, formally triggering Brexit.
The Herald's front page headline is "The beginning of the end", as the paper's UK political editor reflects on Britain's 44-year "rocky" relationship with the European Union.
The Scotsman says that the scale of the task ahead was made clear on the first day of the formal negotiation period as a row erupted over the future of security co-operation in Europe.
The i newspaper says "goodbye" in more than a dozen European languages on its front page, reporting that European Council President Donald Tusk was "solemn and sorrowful" as he received the letter.
The National's front page is directly addressed to Mr Tusk with the message "We'll see you soon #ThatLettersNoMine" - the paper says that Nicola Sturgeon has insisted Scotland will have a choice between independence and a "hard Brexit".
"Day one and the gloves are off" is the front page headline in the Daily Mail, which accuses the EU of "wailing" over Theresa May's threat to withdraw co-operation over security if a deal cannot be reached.
But the Daily Record has a different take on the security issue, declaring the prime minister as "Despicable May", pointing out that the threat came as Westminster held a memorial service for the victims of last week's attack.
The first minister's independence dream is in "tatters" after a survey showed that Scots do not want a special Brexit deal to keep the country in the EU single market, according to the Scottish Daily Express.
The Press and Journal uses Mrs May's declaration that there is "No turning back" as its headline, the paper also saying that the prime minister promised to represent "every person in the whole UK" in the forthcoming negotiations.
The Scottish Sun is the only national paper not to lead on the triggering of Article 50, reporting instead on how a Harry Potter-themed village fete was scrapped when organisers found out 10,000 fans planned to descend on it.
And The Courier has a story on two suspected petrol bomb attacks in Glenrothes, which are being treated by police as attempted murder.