It's likely the little gibbon's family had been killed.
The officials seized the gibbon from traffickers who were trying to sell the little orphan as a pet and called the exact right people - wildlife rescuers from the Laos Wildlife Rescue Center (LWRC) rushed to bring the terrified gibbon to safety. They had to travel hundreds of miles to retrieve him.
The officials, meanwhile, named the little guy Ee Ooo, because of the little sounds he was making to communicate. They also gave him a blue blanket to comfort him while he waited for his rescuers.