US President Barack Obama spoke for many when he said, "All in all, this has been a tough week."

During five days of terror, three people, including a Chinese graduate student, were killed watching the Boston Marathon, and more than 170 others were injured, some horrifically. A police officer at Massachusetts Institute of Technology and one of the bombing suspects were shot and killed. A million Bostonians were locked down in their homes as authorities searched for one of two brothers of Chechen heritage who had been in the United States for a decade and who had turned a well-loved, easygoing city into a war zone.

Out of a clear blue sky at a historic sporting event on Patriots' Day, innocent people were attacked while the world watched, aghast. There was an outpouring of grief for the victims: Lu Lingzi, 23, Martin Richard, 8, and Krystle Campbell, 29, killed in the blasts on April 15, Sean Collier, 26, the MIT police officer reportedly gunned down by the brothers on the night of April 18, and the countless maimed.

There may be psychological wounds that will never heal. But courage and determination were on display. Civilians and first responders ran in the direction of the blasts to help. Exhausted runners made their way to hospitals to give blood. Victims who lost limbs woke up in the hospital and gave thanks for being alive.

And solidarity was expressed by both sides of what is usually characterized in the media as a wary and uneasy relationship.

A Foreign Ministry spokeswoman said the Chinese government was grateful to the US for aiding relatives of two Chinese victims: Lu, the Boston University graduate student from Shenyang, capital of Liaoning province, who was killed when a bomb exploded near the finish line, and her friend graduate student Zhou Danling, from Chengdu, Sichuan province, who was seriously injured.

Following the explosions, President Xi Jinping sent his condolences to Obama, and State Councilor Yang Jiechi and Foreign Minister Wang Yi expressed their sympathy to US Secretary of State John Kerry. In return, Kerry's office said it had been in touch with Lu's family and was ready to provide assistance.

Lu had only been in Boston since September 2012 but the outpouring of public grief in the US over her tragic, early death was particularly striking. It took only 10 minutes on April 17 for the Campaign for Boston University Board of Trustees to raise $560,000 for a scholarship in her memory.

"It has always been her dream to come to America to study," Lu's family said in an open letter published on the university's website. "While she was here, she fell in love with Boston and its people. She loved her new friends and her professors at Boston University. She wanted to play a role in international business, specializing in applied mathematics. She has been studying very hard toward her goal. Sadly, it was not to be."

Thousands of Chinese Internet users expressed their sorrow and condemned the bombings. Lu's death haunted Americans as well. Chris Combs, 25, who had a narrow escape at the finish line, told The Boston Globe: "It is weird when you realize how close you come to something like that. I think about all the people hurt and the people who died, that little boy." He added, "I'm thinking of that Chinese girl who was studying at BU. That's who I'm thinking of."

Tamerlan Tsarnaev and his younger brother Dzhokhar were identified as the suspects. Tamerlan was killed in a shootout with police, while his wounded brother was found in a boat parked in a backyard in the Watertown area of the city. The owner spotted blood on his boat, lifted the tarpaulin and saw the suspect covered in blood.

Bostonians and law enforcement officials breathed a huge sigh of relief while remembering those who were gone and those whose lives were blighted forever.

The extensive Chinese and US media coverage of the marathon bombings highlighted our shared humanity instead of accentuating our differences. It was a tragedy we all had to bear.

The author, who grew up in Boston, is assistant director of the international news department at China Daily.