Editor's note: Solmaz Sharif is Iran Affairs coordinator at cyberdissidents.org. For more than 12 years, she has worked as a journalist for Persian media outlets such as BBC Persian and the Etemad Melli Newspaper. She is also founder of the first Iranian women's sports magazine, Shirzanan.
(CNN) -- Two months ago, Emad Ghavidel turned on the television in Tehran and saw graphic footage of an injured Syrian child crying out in pain.
The 24-year-old Iranian rapper was horrified by the violence and the government's brutal crackdown on Homs. The more Ghavidel learned about it, the angrier he became.
He decided to channel his frustration into his music. He wrote a song, "The Battle of Homs," expressing support for the Syrian protesters and lashing out against the regime of Bashar al-Assad.
"I swear to the laments of grieving mothers, I swear to the tears of grieving mothers, you will pay for it, Bashar al-Assad," raps Ghavidel. "Even if I am drowned in my own blood, I will not shut up."
Within weeks, the song went viral on YouTube and was an instant sensation in the Middle East.
"I received many encouraging messages from both Syrians and Iranians," said Hamed Fard, an Iranian who helped Ghavidel produce the song.
Many Iranians sympathize with the Syrian people, and the two peoples share a common bond, said Ahed al-Hendi, a Syrian who now serves as Arabic Programs coordinator at cyberdissidents.org. In 2009, many Iranians were arrested and tortured -- and some were even killed -- as they protested the disputed presidential election.
"When the Green Revolution was sparked in Iran, we stood with the Iranian people and supported their cause," Al-Hendi said. "Now, lots of Iranians are supporting our cause.
"We are all facing one enemy. The mullah's regime in Iran and the Assad regime (in Syria) support each other openly, and their alliance is very rooted. But we need an alliance between a democratic Iran and Syria, not an alliance of dictatorship."
Iranian President Mahmoud Ahmadinejad recently praised Syrian officials for how they "are managing" the yearlong uprising in Syria. Also, activists claim to have found a series of e-mails that showed al-Assad took advice from Iran on how to handle the unrest. Throughout the uprising, the Syrian government has described opposition leaders as terrorists looking to destabilize the country.
To date, more than 9,000 people have been killed in the conflict, according to the United Nations.
"As a human and a journalist, it is unbearable to witness this crime," said Sasan Aghai, an Iranian who works for the Sobh-e Azadi newspaper. "Everyone around the world who cares about human rights should be bothered by what it happening in Syria. It's genocide."
This is not Aghai's first foray into political activism. As an active supporter of the Green Movement, he was arrested for "activity against the country's security" and spent time in Evin prison, the notorious prison for Iran's political dissidents.
Artists were also among those arrested. Aria Aramnejad, a young Iranian pop singer, was taken into custody after he posted a song on YouTube in support of the Green Movement.
Ghavidel is keenly aware of the risks he faces as a rapper. Iran's Ministry of Islamic Guidance does not consider rap an art form, so no Iranian rapper can get government permission to record a song.
"All Iranian rappers work underground," he said. "We all have difficulties recording and distributing our songs, but I don't let these problems stop me.
"People ask me if I'm worried about the consequences of my song, but I don't believe I've said anything wrong. I want to hope that there is enough freedom of speech in my country that I can criticize a mass murder."
Such support has not gone unnoticed by the Syrian opposition. The Syrian National Council recently published a letter thanking the citizens of Iran.
"It is important for all of us to know that we share one region and that our struggles and freedoms are connected," the letter said. "The Syrian and Iranian regimes have cooperated very closely throughout the years to oppress their own people and to destabilize the region around them. We believe that the only way that our people can prosper is by cooperation and mutual respect to each other's past, present and future aspirations."
Would a Syrian revolution have an effect on Iran? Aghai thinks it is unlikely.
"I don't think the Syrian revolution will result in an Iranian revolution as well," he said. "But after losing one of its good allies in the region, we can say that the power of the Iranian regime will start to fade."