New York (CNN) -- A New York man arrested in connection with the stabbing of two children in Brooklyn may be linked to another stabbing in a Manhattan subway, a law enforcement official told CNN Thursday.

Police believe Daniel St. Hubert, 27, was out on parole when he stabbed two young children inside an elevator -- killing one of them.

St. Hubert was arrested by detectives around 8 p.m. Wednesday.

He was arrested around the same time that Chief of Detectives Robert Boyce identified St. Hubert by name for the first time as the suspect in the attack.

Detectives were obtaining evidence Thursday that could link him to a fatal stabbing on the subway in the Chelsea neighborhood of Manhattan, the official said.

Investigators were executing search warrants to see if he is linked to additional stabbings since his release from prison on May 23, a law enforcement official said.

Law enforcement has been involved with St. Hubert plenty in the past, including nine arrests, though police did not specify all the outcomes.

The most recent instance was May 23, when, Boyce said. St. Hubert was released on parole in connection to a domestic assault case.

Nine days later, police believe he encountered 6-year-old Prince Joshua "PJ" Avitto and 7-year-old Mikayla Capers inside an elevator at a public housing complex in Brooklyn. Mayor Bill de Blasio said the two children were "on their way to get ice cream" at the time.

For reasons authorities haven't yet explained, the two children were stabbed -- both in the torso. PJ Avitto was transported to a nearby hospital, where he was pronounced dead.

1. Who was arrested?
2. When?
3. Was he in prison earlier?
4. before when?
5. How many arrests he had?
6. Who is Boyce?
7. What he identified?
8. For what?
9. For what reason?
10. suspect for what crime?
11. What are their names?
12. How old was Prince?
13. And Mikayla?
14. Where were they killed?
1. Daniel St. Hubert, 27
2. around 8 p.m. Wednesday
3. yes
4. May 23
5. nine arrests
6. Chief of Detectives
7. he identified St. Hubert by name
8. for the first time
9. to identify him as the suspect
10. the stabbing of two children
11. Prince Joshua and Mikayla Capers
12. Six
13. Seven
14. inside an elevator