The Beijing Public Security Bureau said that it had arrested a man who police believe attacked women with a blade in the subway.

The man, surnamed Hu, is suspected of cutting several female passengers' faces on the city's subway lines 5 and 10. He was caught on Thursday, according to a statement on the police force's micro blog on Thursday night.

During the preliminary investigation, the suspect, 25, from the city's Chaoyang district, confessed and said he had an emotional frustration, the micro blog said.

The man is accused of attacking five women, one of whom needed 15 stitches.

Zhao Feng, a police officer working in the bureau's information office, said on Friday that the case was still being investigated. He provided no further details.

One of the injured women, whose Internet name is Miss Nabao and who did not want to be identified by her real name, said her face was cut when she was standing next to a gate of a train at Guomao station of Line 10 on Wednesday.

She was scared and her face was bleeding, she said.

"I'm fine now and glad to see the suspect has been caught," she said.

Before the arrest, the suspect's description and photos were posted on the Internet.

Cui Shaoyu, 24, an employee at a media company who takes subway Line 10 from Guomao station to Tuanjiehu station every day, said she is still worried, even though the suspect has been arrested.

"When I first heard of the case through my micro blog, I thought it was fake, because sometimes online news is exaggerated," she said. "But I finally believed it after some portal websites published witnesses' photos with blood.

"What I can do is maybe just pay more attention to those who behave oddly," she added.

Sun Yue, 24, another Beijing resident, has the same concern. She works in a travel agency and takes Line 5 every day from Liujiayao station to Beixinqiao station.

"At first I thought the man wanted to steal those women's cell phones, but after I got the truth, I was shocked. It's crazy and unbelievable," she said, adding that she will not stand near the subway's gates where the victims were injured.

Zhang Yu, a Beijing-based criminal lawyer with Shangquan Law Firm, said the suspect's self-described "emotional frustration" cannot be used as a reason to give him a light punishment.

"The man committed the same attacks several times, which will also affect his sentence if the case goes to trial," he added.

The lawyer also suggested that subway management install more surveillance cameras.

A security guard who refused to give his name at Huixinxijie Nankou station on Line 5 said that knives longer than 10 cm in a bag can be detected by security-check equipment.

"We'll confiscate the knives and contact the police. But if passengers carry knives themselves, it's hard to check," he said.

Zhao Guifang, an associate professor specializing in criminal psychology at the Chinese People's Public Security University, said it is an extreme individual case. "Some people with trouble in their love lives may mutilate themselves, but some may injure strangers who are trying to protect themselves. The latter attack people with a similar appearance and age as their lover, hoping to get a reaction," she said, adding that such extreme behavior has happened in the capital before.

She added that such people need mental counseling and support.

Zheng Jinran contributed to this story.

Contact the writer at caoyin@chinadaily.com.cn