On the one-year anniversary of the deadly terror attack in Brussels, people in Belgium and around the world are reaching out to send a message of solidarity to the victims of the U.K. Parliament attack in London on Wednesday.

“Today, we remember the victims of the attacks. We are all united,” Belgium’s prime minister Charles Michel wrote on Facebook just hours before chaos struck London at approximately 2:40 p.m. local time.

Britain’s Parliament was put on lockdown after officials say an assailant stabbed an officer, then was shot by police. About a dozen people were also struck by a vehicle that apparently mowed down pedestrians on nearby Westminster Bridge. Police say at least four people were killed, including the attacker and a police officer, and 20 people were injured.

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Police said they are treating it as a suspected terrorist incident. The latest tragedy comes exactly one year after 32 people were killed in suicide bomb attacks on the Brussels airport and subway.

To demonstrate their solidarity, Twitter users shared illustrations, cartoons and thoughtful words with the hashtag #PrayForLondon, which has already been used by more than 75,000 people.

People prayed for peace for both Brussels and London:

One year on exactly from last years Brussel bombings, and our country is under attack too. Praying for a world of peace #PrayForLondon ❤ — Brooks Way (@brooks_way) March 22, 2017

#PrayForLondon One year after Brussels again terrible news. London terror attack 😤 Sad sad times pic.twitter.com/RswXEw2bRH — 🌸Bar 🌸 (@BarbaraBosch) March 22, 2017

And spread the word that attacks “will not break us”:

Thoughts are with the victims of this horrific attack and emergency services,you will not break us but bring us together #PrayForLondon ❤🙏🏻 pic.twitter.com/9WqRwCEBhJ — bethan💫 (@suggftelmo) March 22, 2017

london stays strong, we are not afraid #PrayForLondon — ☼ (@illucination) March 22, 2017

#PrayForLondon #Westminster Terrorism and Violence wil only bring us closer together till we wipe out hatred and evil for Love + Compassion pic.twitter.com/4YmNdfxs28 — T.Y.🏳️‍🌈 (@Tabapugh) March 22, 2017

Others simply offered their prayers and condolences:

Sad day. My thoughts are with the victims and all those affected by today's attack in London. #PrayForLondon 🇬🇧#Westminster pic.twitter.com/axzho78ha3 — Aly Deminne (@AlyDeminne) March 22, 2017

So sad...so unnecessary. My heart goes out to the victims and their families 💔#PrayForLondon pic.twitter.com/UEDzNygwND — tara strong (@tarastrong) March 22, 2017

My Thoughts and Prayers for the Victims and Families. All this violence needs to stop 🙏🏾#PrayForLondon 🙏🏾 pic.twitter.com/EHEcQBc1ES — Nicola Adams (@NicolaAdamsOBE) March 22, 2017

Last year, a cartoon of the national flag of France comforting a sobbing Belgium flag quickly became the symbol of solidarity for Brussels. Underneath the teary-eyed flags, read the words: “13 novembre...22 mars...” -- a reference in French to the dates of the Brussels and Paris attacks.

The photo, shared by French cartoonist Jean “Plantu” Plantureux, who called it the “drawing of the world,” went viral with nearly 12,900 retweets.

In wake of the London attack, Italian artist and graphic designed Diego Cusano‏ created his own drawing to represent the grief and mourning people around the world are feeling. It’s a sketch of the Big Ben clocktower in London covered with a single teardrop.

“London stay strong!” he wrote.

“My life is made of emotions and I express myself with drawings and images,” Cusano told CBS News. “Whenever I have an emotion, whichever it is, I need to express it with my works.”

Like the rest of the world, Cusano said he was shocked by the incident in London, and said he wanted to express his sorrow and condolences to the victims’ families and to the whole nation “in my way, with my style.”

To expand their reach beyond London, Twitter users also began to use the hashtag #prayfortheworld.

“#PrayForTheWorld it doesn’t just happen where it’s covered by the news - pray for everyone everywhere because it does not stop here,” one Twitter user wrote.

“#PrayForLondon but remember to #prayfortheworld ... do not spread hatred nor wish it on anyone else,” another tweeted.

Cusano hopes his drawing and message resonate with the rest of the world. After all, “we are all suffering in the same way,” he said.