About 43 people were killed on Sunday night by a group of armed men who attacked a market in northwest Nigeria, local authorities announced Monday evening, after it indicated earlier that dozens were killed.

"It has been confirmed that 43 people were killed in an attack by gangs on Goronyo village in Sokoto state," Sokoto government spokesman Muhammad Bello said in a statement on Monday evening.

"The gunmen stormed the market while it was full of buyers and sellers," a trader told Reuters. "They were shooting at us randomly after they surrounded the market and started shooting in every direction and killing people."

For years, these groups, which residents call "bandits", have been spreading panic in northwestern and central Nigeria.

In recent months, the violence of these gangs has escalated, plundering villages, stealing livestock and carrying out kidnappings for ransom.

At least 19 people were killed 10 days ago in an attack on a market in another village in Sokoto state in the Sabun Berne region, near the border with Niger.

The attack may be in retaliation, as 11 people were killed in a market in a neighboring village by a civil group formed for self-defense against these groups.

Reports of attacks in the northwest often arrive late, as authorities suspended communications last month in Zamfara and parts of Katsina, Sokoto and Kaduna states.