BOSTON //It was his first Boston Marathon experience since moving here from Dubai last year, and Marwan wanted to get to the finish line to soak up the atmosphere. But the crush of people made it impossible so he went into a shopping mall near the finish line for a sandwich instead.
Marwan, a 22-year-old from Lebanon, and a Pakistani school friend were making their way through the high-rise building's food court when there was muffled boom. The building shook for a few seconds, then there was confused silence.
"I thought it was an earthquake or maybe a cannon blast at the end of the race but I walked outside to see what was going on," said Marwan, a first-year architecture student. "Then everything started going in slow motion, like a movie."
White smoke filled the air and people in the food court began to scream and panic, thinking the explosion had happened in the mall. There was a stampede to go outside on to Boylston Street, and a people rushing in to the mall from the finish line where the two bombs had just torn through onlookers.
Marwan moved a safe distance away and began calling family members to let them know they were all right. Marwan spoke to his mother loudly in Arabic. "But then Zheela [his friend] nudged me and said 'speak in English', and that's when it hit me: speaking Arabic is suspicious now," he said.
It is the fear of Arabs and Muslims in the US that if an Islamist link to Monday's bombings is discovered, there will be a return to the months and years after the September 11 attacks when hate crimes spiked and when government brought in policies such as a federal programme - no longer in place - which required foreign Muslim men to register with police.
While there is no evidence that suggests the perpetrator was a Muslim, Islamic organisations in the US jumped into action hours after the blasts, issuing statements that voiced their solidarity with the victims, and, in Boston, offering to help in whatever ways possible.
The Islamic Society of Greater Boston Cultural Centre offered its resources to state officials, including counselling services. About 50 of its members donated blood for victims in the hours after the attacks. "In Boston, in the Muslim and Arab community, there is a huge concentration of physicians, so a lot are already involved in taking care of the injured, and there are attempts to try to have physicians volunteer in some organised way," said Hesham Hamouda, a staff psychiatrist at Boston Children's Hospital.
Fears rooted in the post-9/11 experience returned after early media reports said a Saudi student, who was taken to hospital after the bombing, was questioned by officials. He was later cleared.
"Speaking as an Arab Muslim who lives in Boston, there are fears we share with the larger community. There is shock, because Boston is a very peaceful city," Mr Hamouda said. "But there are also feelings that are unique to our community, and I think everybody at the bottom of their hearts is hoping and praying this was not perpetrated by an Arab or Muslim."
Sahar Aziz of the Institute for Social Policy and Understanding, a US think tank, told Agence France-Presse that Muslims should be wary, especially if their fears are realised and the bomber happens to be Muslim.
"Because the stereotype of Muslims as terrorists and disloyal has become entrenched within American culture, there is a strong likelihood that Muslims in America will face backlash if the suspect … is a Muslim.
"Such backlash could take the form of hate crimes, mosque vandalisation, evictions from airplanes, school bullying, and scapegoating in certain media outlets," she said.
But Marwan said he was not sure that the reopening of the psychological wounds of 9/11, even more than a decade later, would be closed so easily, even if the bombing was found to be carried out by domestic terrorists.
"It doesn't mean the city of Boston is going to relax," he said. "It's going to take a while."
"The first time I came to the US was in 2008, and people seemed like they had forgotten, I never received racist comments," he said. "But I think people are now remembering the same feelings they had back then [in 2001]."
Already yesterday, he said he felt a subtle change. At a restaurant he again slipped into Arabic and people began to stare. "I feel like I have to be extra careful, and that's new since Monday."
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