SEOUL, South Korea — A man stabbed at least eight people at a shopping mall in the South Korean city of Incheon, police and fire officials said Tuesday.

Incheon’s Namdong District Police Station detained a 59-year-old suspect whom they say attacked shoppers as he moved through the mall before bystanders subdued him.

It wasn’t immediately clear why he carried out the attacks.

The injured were taken to nearby hospitals, including one woman in her 20s who underwent surgery after arriving in cardiac arrest, Incheon’s fire department said. The department didn’t immediately provide details on the severity of the other injuries.

South Korea’s Yonhap news agency quoted a witness as saying the suspect appeared to have knives strapped to both hands. The witness said the man began stabbing people at a discount store on the mall’s basement level and continued attacking others as he moved up an escalator before being subdued by several people.