At least 23 people were killed and six others sustained minor injuries after the gunmen attacked the bus, the motive for which was unclear.
Gunmen in Nigeria have attacked a bus in the country's northwestern Sokoto state, causing a fire that killed 23 civilians.
"23 people lost their lives," said the governor's spokesman Muhammad Bello on Wednesday.
The bus was travelling from the small village of Gidan Bawa in Sokoto, near the border with Niger, down to Kaduna state on Monday, said Bello.
"Of the total number of people in the bus which the bandits shot at causing a conflagration, 23 died of fire burns," the statement added, quoting the state police commissioner, Kamaldeen Okunola.
Six others sustained minor injuries and are receiving treatment, he added.
"Security agencies mobilised to the spot of the attack and immediately mounted a patrol that is still ongoing," said Okunola.
It was unclear why the bus was attacked but heavily armed criminals, known locally as bandits, have for years terrorised northwest and central states in Africa's most populous nation.
Violence on rise
Since last year, bandit gangs have become more violent.
This year alone, more than 1,400 children were kidnapped by bandits according to UNICEF.
Since January 2020, more than 57,000 people fled from their homes in northwest and central Nigeria due to insecurity, according to the International Organization for Migration.
More than 80,000 additional people have fled to neighbouring Niger over the past two years.