At least three people were killed and five injured in the Taiwanese capital, Taipei, in attacks at two metro stations on Friday.

The perpetrator, a man said to be in his twenties, was initially thought to have jumped to his death from a nearby building after the attack.

That fact was later confirmed by police, who said he had been certified dead after he was sent to the hospital, according to Taiwan's Central News Agency, bringing the total number of dead to four. 

What happened in the Taiwan metro attacks?

The attacks took place at two metro stations in Taipei. Here's what we know so far based on footage carried by broadcaster EBC and authorities' remarks:

• A masked person threw gasoline bombs or smoke grenades at Taipei Main subway station
• The perpetrator rode the subway for one stop before exiting the station and throwing more smoke grenades on the street
• Outside, he started wielding a knife at pedestrians before running into a shop

It is unclear how the attacker got to a rooftop of a building, from which he jumped to evade arrest. 

Police say several individuals were not only injured in the knife attack, but also by the smoke grenades.

Taipei Mayor Chiang Wan-an said one of the victims was killed while trying to stop the attack. 

What do we know about the suspect?

Taiwanese Premier Cho Jung-ta called the attacks "a deliberate act," adding that police had increased security at Taiwan's train and subway stations.

Authorities said the suspected attacker had a ‍criminal record and outstanding warrants.

On Saturday, authorities said the 27-year-old suspect had planned the attack, adding that investigations revealed he acted alone.

“The suspect planned an indiscriminate attack. He acted according to his plan,” said Chang Jung-Hsin, director-general of the National Police Agency.

Cho said investigators had searched the man's ​home, adding, "We will investigate his background and associated relationships to understand his motives and determine if there are other connected factors."

Taiwanese President Lai Ching-te said the government would strengthen security and swiftly investigate the case to ensure public safety.

How did Taiwan's President Lai Ching-te react?

Taiwan's President Lai Ching-te visited the victims of the attack in hospital on Saturday, condemning the "horrific, violent attacks" and saying he "ordered a "full and thorough investigation" and would "give the public a full account of the truth."

Lai told a police briefing also on Saturday that authorities should be "more cautious and proactive."

"Once a call or message is received, the rapid response force must arrive as quickly as possible and must be capable of stopping such attacks," he said, adding that Taiwanese security forces must be "trained and equipped for counter-terrorism operations" to protect citizens.

Edited by: Wesley Dockery