BANGKOK -- Thai police have arrested the driver of a bus carrying young students and teachers that caught fire and killed 23 in suburban Bangkok, as families arrived in the capital Wednesday to help identify their loved ones.

The bus, carrying six educators and 39 students from elementary and junior high schools, was en route from Uthai Thani province, approximately 300 kilometers (186 miles) north of Bangkok, for a school field trip to Ayutthaya and Nonthaburi provinces on Tuesday. The fire broke out while the bus was on a highway north of the capital, spreading rapidly, preventing many from escaping.

Trairong Phiwpan, head of the police forensic department, stated that 23 bodies were recovered from the bus. Retrieval efforts and confirmation of the total fatalities were delayed earlier because the burned vehicle, powered by natural gas, remained too hot to access for several hours.

The families were transported from Uthai Thani to the forensic department at the Police General Hospital in Bangkok on Wednesday in vans to provide their DNA samples for the identification process. Kornchai Klaiklung, an assistant to the Royal Thai Police chief, informed reporters that the forensics team was working diligently to identify the victims.

The driver, identified by the police as Saman Chanput, surrendered on Tuesday evening, several hours after the fire. Police officials stated they have charged him with reckless driving resulting in deaths and injuries, failing to render assistance to others, and failing to report the accident.

The driver informed investigators that he was driving normally until the bus lost balance at its front right tire, colliding with another vehicle and scraping a concrete highway barrier, which ignited the blaze, according to Chayanont Meesati, deputy regional police chief, who spoke to reporters.

The driver explained that he ran to retrieve a fire extinguisher from another bus traveling on the same trip but was unable to extinguish the flames. He then fled due to panic, said Chayanont.

Police authorities are also investigating whether the bus company adhered to all safety regulations.

In a statement to Thai PBS, Songwit Chinnaboot, the owner of the bus company, stated that the vehicle underwent routine safety checks twice annually as mandated by regulations. He also assured that the gas cylinders had met all safety standards. Chinnaboot further expressed his commitment to providing financial assistance to the families of the victims to the best of his ability.

Three students are currently receiving treatment at the hospital, with two of them listed in critical condition. A 7-year-old girl sustained facial burns, and a surgeon reported that medical personnel are diligently working to preserve her vision.