Wadi Khaled, Lebanon - Mohammad al-Sheikh woke up, like most nights, to the intense sounds of bombardment coming from Syria. The 15-year-old began, quietly, to pack a small suitcase in the dark. Before sneaking out of the house in this Lebanese border region, he took a final look into the living room, thinking it would be the last time he would see the place in which he grew up. The skinny schoolboy was heading to Syria to pursue jihad.
The atrocities unfolding just a few kilometres away from his family's home had become too much for him to take. The Lebanese boy had spent the past two years watching from his window as fighter jets hovered over the green terrains of Syria, and thick, black smoke rose from villages in which he had spent many of his holidays.
Footage of blood and misery emerging from the conflict and horror stories from Syrian refugees continued to haunt him. Calls of clerics on YouTube urging men to join the fight against President Bashar al-Assad rang in his ears.
Following the footsteps of several teenagers in Wadi Khaled who dropped out of school to join the fight in Syria, Mohammad left the northern valley at dawn to become a rebel fighter.
When Mohammad's father, Ahmad al-Sheikh, woke in the morning and found the empty bed of his son, he quickly recalled his son's repeated threats to go to Syria - every time he fell out with his parents. The father, a local politician, contacted the Lebanese military to stop his son from crossing the border.
Mohammad was arrested at a checkpoint at the entrance of the village of Arsal, which borders the mountainous Syrian Qalamoun region.
But instead of handing over the child to his family, as the father had assumed, the military took Mohammad to a defence ministry detention centre in Beirut, where he said he was beaten up and humiliated for six days.
Mohammad's interrogators found downloaded photos on his mobile phone of fighters from Jabhat al-Nusra, al-Qaeda's Syrian branch, and from other self-declared "jihadist battalions" operating in Syria.
"They called me a terrorist while stepping on my head," he told Al Jazeera.
"When they asked me why I was going to fight Syria, I said: 'Just like Hezbollah is fighting in Syria.' So they beat me up even more."
Scores of Lebanese Sunnis, like Mohammad, have smuggled themselves into Syria to fight alongside overwhelmingly Sunni rebels in Syria. The Lebanese Shia movement, Hezbollah, meanwhile, has reportedly sent thousands of fighters to support Assad's military. The Syrian president and many in his government come from the Alawite sect, an offshoot of Shia Islam.
"Hezbollah goes to Syria to kill Syrian people and when its members die there, their funerals are held publicly through the border crossings. Sunnis, on the other hand, are captured and tortured if they think of going to Syria," Mohammad, wearing a hooded navy sweatshirt, told Al Jazeera.
His detention has deepened his sense of marginalisation as a Sunni, allowing him to feel even more justified in wanting to fight in Syria: "Supporting the oppressed Sunnis and advancing the cause of Islam in the Levant."
|Mohammad's father believes the boy was 'brainwashed'
by social media videos [Basma Atassi/Al Jazeera]
Mohammad's father, while overwhelmed with guilt for contacting the military forces, said he had no way to suppress his anger against his son after his release. He banned the boy from staying out late, took away his mobile phone and unplugged the internet.
He believes his son has been exposed to extremist rhetoric and "brainwashing".
"All he talks about is jihad and the 72 virgins that he will be rewarded with after martyrdom," Ahmad, told Al Jazeera.
"We are proud Muslims, but we are moderate. We have Shia friends and Alawite friends. We hate extremism and sectarianism."
He said he was not against those who wanted to fight in Syria, but he believed his son and other children are being taken advantage of.
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"I tried to find out who is teaching him all of this, but I couldn't." He paused for a moment, then added: "If the interrogators who put him under duress for six days couldn't, how could I?"
The local politician said he had warned the government about the rise of extremism in Wadi Khaled more than two years ago during a televised interview. He said the marginalisation by the government of Wadi Khaled, where unemployment is high and people live in relative poverty, would become a hub for al-Qaeda's influence. But he did not expect that influence to invade his own home.
"I was an artist, not a religious preacher," he said. "How my son became like this I have no idea."
The economic isolation of Wadi Khaled can be traced back decades. The population was made up of stateless Bedouins, whose status was considered "under study" after a historical mishap left them with no citizenship rights. They depended on smuggling goods across the Syrian border to make a living, and have developed strong ties to people in the neighbouring country.
Many Wadi Khaled residents only obtained Lebanese nationality in 1994, based on a decree issued that year.
"People of Wadi Khaled lived in injustice," said Ahmad. "So we sympathised with the revolution in Syria and all the revolutions that happened throughout the Arab world."
Imad Mlabbes, an imam in Wadi Khaled's mosque, has recently tried to focus his weekly sermon on urging young men and boys to avoid travelling to Syria.
"I always tell them Syria does not need more men. There are enough fighters there," he said.
Young untrained men heading to Syria are not only useless on the battlefield but will also give Hezbollah a justification to send more of their fighters, who are trained and well-equipped, Mlabbes said.
But he acknowledged that a lot of boys remain hard to convince to stay. They are learning "the wrong Islam" through social media, said the imam.
The owner of a butcher shop in the area said his young brother had been downloading chants and lectures "that instigate youth to go to jihad", and listened to them for hours every day.
"My father has confiscated all my brothers' travel documents, in case any of them decide to run away," he told Al Jazeera.
But Mohammad said it took neither chants nor lectures to choose "to seek martyrdom" in Syria.
"The images of massacres in Homs and Aleppo are beyond what the mind can withstand," he said. "It's enough of an instigator [to make] anyone fight the Syrian regime."
Follow Basma Atassi on Twitter: @Basma_