A year after the deadly Boston Marathon bombings, the northeastern US city will pay solemn tribute to the victims of the attack.
The solemn ceremonies will take place at the scene of the carnage at one of the world’s sporting events – in the heart of the city, on Boylston Street.
Church bells will toll at 2.49pm (0449 AEST Wednesday), the moment the first bomb exploded at the race’s finish line on April 15 last year.
The two pressure-cooker devices allegedly planted by two brothers of Chechen descent, who had lived in the US for years, sent metal fragments flying through the crowd, killing three people and wounding more than 260 others. Several people lost limbs.
Dzhokhar Tsarnaev, who is now 20, and his 26-year-old brother Tamerlan were identified thanks to pictures and video footage and eventually cornered by police after a four-day manhunt that paralysed the city of nearly one million.
Tamerlan died after an exchange of fire with police, and Dzhokhar was wounded and captured. The younger Tsarnaev, a naturalised US citizen, will go on trial in November and could face the death penalty if convicted.
US Vice President Joe Biden, Massachusetts governor Deval Patrick, Boston mayor Martin Walsh and his predecessor Tom Menino – who was in office at the time – will speak at the event at the Hynes Convention Center, along with survivors.
Tuesday’s tribute ceremony “will honour those affected by last year’s events, including those who lost lives, survivors, and first responders”, organisers said.
There will be a flag-raising ceremony and a moment of silence will be observed at the race’s finish line.
This year, the Boston Marathon – which has been run since 1897 – will take place on Monday, April 21.
Organisers have allowed thousands more runners to register – from about 27,000 in recent years to 36,000 this year, not far from the record 38,708 who entered in 1996 in the 100th marathon.
Dzhokhar Tsarnaev has pleaded not guilty to 30 federal charges related to the bombings, including 17 serious charges that can carry sentences of death or life in prison.
The charges include using a weapon of mass destruction resulting in death, as well as conspiracy and bombing of a place of public use resulting in death, and carjacking.
Tsarnaev is also charged in connection with the fatal shooting of a campus police officer at the Massachusetts Institute of Technology during the brothers’ wild getaway attempt.