BERLIN (NYTIMES) - Anis Amri, a Tunisian man who turned 24 on Thursday (Dec 22), is the chief suspect in a Europe-wide investigation into Germany's worst terrorist attack in decades.

His fingerprints and identity document were found inside a tractor-trailer that crushed into a Christmas market in Berlin on Monday, killing 12 people and injuring about 50 more.

Here is a timeline of events in Amri's life, drawn from government statements, interviews with officials and relatives, and news media accounts.

Dec 22, 1992: Amri is born in Oueslatia, a town in the mid-west region of Tunisia, the youngest in a family of five sisters and four brothers. He drops out of secondary school at 14 and gains a reputation for drinking, partying and playing music.

March 2011: Amri leaves with three friends by boat for Italy a few months after the start of the political uprising that overthrows Tunisia's long-time president. He is later convicted in absentia by a Tunisian court for stealing a car and sentenced to five years in prison.

Oct 2011 to May 2015: He is arrested in Belpasso, Italy - a small town on the east coast of Sicily - and is sentenced to four years in prison for causing a fire, damaging property and making threats, according to the Italian Justice Ministry. Local news outlets report that three Tunisian asylum seekers, including a 19-year-old with the initials A.A., were arrested for setting fire to the centre where they were staying to protest against poor living conditions and delays in the processing of their asylum claims. Italian prison records show he spent nearly four years in a total of six prisons.

July 2015: Amri enters Germany. According to Mr Ralf Jager, the interior minister of North Rhine-Westphalia, Germany's most populous state, Amri is "highly mobile" over the next few months, passing through Freiburg, a city in the south-west, Berlin, and North Rhine-Westphalia.

February 2016: Amri settles in Berlin, according to Mr Jager. His sisters said he finds work in construction and as a cook.

March 14, 2016: Authorities in Berlin open a file on Amri because of "indications from the federal security authorities" that he was a potential threat. He had evidently planned a robbery to get money to buy automatic weapons, "possibly in order to carry out an attack", the prosecutor said. Undercover surveillance, including electronic monitoring of Amri's movements, begins. The surveillance leads the authorities to believe that Amri is involved in drug dealing in the city's notorious Gorlitzer Park. Prosecutors said that at one point, he got into a fight in a bar after a quarrel with another dealer.

September 2016: The monitoring of Amri ends, for reasons that are not clear.

April 2016: Amri reportedly makes a formal application for asylum in Germany.

June 2016: Amri is ordered deported. But, according to Mr Jager, he cannot be sent back to Tunisia because the country does not acknowledge that he is a citizen and he does not have a valid passport.

July 30, 2016: Police in a town on the border with Switzerland detain Amri after checking the documents of passengers on a bus heading for Zurich. Given the deportation order, and the fact that it is a Saturday, a court orders Amri held for 48 hours in a local jail.

Aug 1, 2016: Amri is released early, according to the director of the jail, Mr Thomas Monig, on the order of the office responsible for dealing with foreigners, because it has no way to carry out the deportation.

Nov 8, 2016: German authorities detain Abu Walaa, a Salafist preacher known as the "man without a face" because he never faces the camera when delivering video sermons, and a German-Serb identified as Boban S. German media reports say Amri was a guest several times at Boban S's home.

Dec 19, 2016: Shortly after 8 pm local time , a truck apparently hijacked by Amri careens into the Christmas market in Breitscheidplatz, a main public square in Berlin. Among the 12 people killed in the market are the Polish driver of the truck, whose body is found inside the truck; an Israeli visitor; and an Italian working in Berlin.

Dec 21, 2016: A warrant is issued for Amri's arrest; a reward of 100,000 euros (S$151,336) is offered for information leading to his capture. The Tunisian passport for Amri that the German authorities said was necessary for him to be deported finally arrives in Germany, months after it was requested.

Dec 22, 2016: The authorities conduct raids at several homes associated with Amri, as well as a Muslim cultural centre and prayer room. They also search a bus in Heilbronn, a city in south-western Germany. The federal prosecutor's office announces that Amri's fingerprints were found on the driver's door of the truck and on the B-pillar, one of the upright structural supports on the side of the cab.