Earlier, camouflaged by his school uniform, the teenager had managed to hide in a heap of cut grass as the group of schoolchildren he was abducted with were taking a break from their forced trek.
More than 280 of them were snatched last week from a school in the town of Kuriga, in Kaduna state, traumatising a community.
"We saw motorbikes on the road. We thought they were soldiers, before we realised they had occupied the school premises and started shooting," Musa tells the BBC as he recalls Thursday morning's terrifying events. We have changed his name for his own safety, along with that of another kidnapped boy mentioned in the article.
"We tried to run away, but they chased us and caught us. They gathered us like cows into the bush."
These armed men on motorbikes - referred to locally as bandits - had been menacing the community for some time, with the security forces apparently unable to deal with the threat. Kuriga had been persistently attacked by gangs seeking to kidnap people and make money from ransom payments.
The scale of this latest abduction and the fact that it involved children as young as seven has been overwhelming for many here.
"We watched them carrying our children away just right here and there's nothing we could do. We don't have military, we don't have police in the community," a distressed Hajiya Hauwa says, through tears.
Musa was one of those taken away.
"While we were moving in the bush, at some points, we were all thirsty, but there was no water. Some girls and boys were just falling as we moved because they were all tired," he says.
"The bandits had to carry some of them on the bike."
At one point, deep into the bush, they were able to quench their thirst at a river which came as a big relief for the children who had not had breakfast and had been forced to walk for several hours under the hot sun.
Musa kept looking for ways to escape and tried to encourage others to join him but they were too afraid.
He saw his chance as the sun was setting. Looking around to ensure he was not being monitored, he hid in one of the heaps of grass and lay still.
"After all was quiet, [to avoid detection] I started dragging myself like a snake on the ground." Once it was totally dark, he got up and walked off until he got to a village where he got help.
He took a huge risk that could have led to him being killed at the slightest mistake, but some are saying that God protected him.
When he appeared the next day in Kuriga, his parents were jubilant, but he came with harrowing tales of the children still in captivity.
The parents of 10-year-old Sadiq Usman Abdullahi are still waiting for news about him.
The last time the family saw the jovial and much-loved boy was when he had dashed back home on Thursday morning saying he had forgotten his pencil for school - shortly before the kidnappers drove into the town.
"He came to ask me: 'Hassan do you have a pencil?'" his 21-year-old brother says.
"I told him to check my bag. Sadiq was in a rush, so he scattered my things. He found the pencil. I told him to tidy my bag. Then he took his socks and ran out."
His mother, Rahmatu Usman Abdullahi, says she has not been able to sleep since that day.
"I always think about him, I can't sleep. What kind of sleep can I even have? Look at my eyes! What kind of sleep? May God just help us," she says, looking up to seek divine intervention.
But Musa and Sadiq are just two among the more than 4,000 people who have been kidnapped in Nigeria in the past eight months, according to one estimate.
In the last decade and a half, people in northern Nigeria have come under intense attack by armed militant groups.
At first, this mainly happened in the north-eastern states of Borno, Adamawa and Yobe, where the Islamist group, known as Boko Haram (meaning "Western education is forbidden") is active.
A second force, linked to the Islamic State group, has also emerged.
Both sets of jihadist groups were involved in kidnapping, targeting farmers, travellers and even razing villages to the ground.
Schools, seen as the home of Western education, became a target. The notorious attack on the girls' school in Chibok 10 years ago set a template.
"There has been an escalation in attacks on schools in northern Nigeria. Primary schools, secondary schools and universities have come under attack," says Shehu Sani, a former senator for Kaduna state. He argues that the aim is to discourage parents from sending their children to school.
"At the same time, when they attack and kidnap, they do it with the intension of raising funds - to buy more arms and also to continue their criminal activities."
But their methods have spread across the north with the criminal gangs known as bandits adopting the same approach, as they have seen that kidnapping schoolchildren often attracts attention, and therefore ransoms.
"They are motivated by money. They simply kidnap people, and once ransom is paid to them, they release their hostages. They have no political agenda and no clear-cut leadership," Mr Sani says.
The government has invested a lot of time and money in tackling the issue, but there are still communities that feel unprotected.
Kuriga is one of those.
Jibril Gwadabe, a local traditional chief, says that the place is plagued by the bandits, due to the absence of security forces in the area.
"I have been a victim myself," the 64-year-old says.
"I was going to my farm one day, two years ago when they stopped me. I started struggling with them and they shot me in my stomach. The bullet came out from my back. I was hospitalised for one month here in Kaduna, but I survived."
The authorities have promised that the children will soon be returned home alive. But people in Kuriga are still worried.
"We don't know the condition of our children up till now. We don't know how they are, where they are," Chief Gwadabe says.
By Chris Ewokor, BBC
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