Responding to journalists' questions about the incident, the president said that he had not yet been briefed on the circumstances of the murder.

He also promised that all details regarding the murder of 23-year-old Ukrainian refugee I. Zarutka will be clarified in the near future.

"This is horrible. I had never heard of this... I will watch the video and have all the details by morning," he said.

Circumstances of the crime

We remind you that on the evening that ended tragically, the Ukrainian woman boarded the train wearing her work uniform. She can be seen slumped in a seat in front of a dark-skinned man, with headphones in her ears.

Sitting behind him was reportedly 34-year-old Decarlos Brown.

The man struggled for a while, then suddenly stood up and raised the knife over the Ukrainian woman's chair. The video is paused at this point because that's when the execution took place - the man stabbed her three times. One of these stabs was fatal.

The man then walked towards the train door, carrying a knife dripping with blood. He quickly took off his sweater.

This post was made public by authorities.

The killer got off at the next stop, where police later found a knife near the platform. He himself was treated for a cut on his hand, but was soon arrested and charged with first-degree murder.

Court records show Brown has a long criminal history dating back to 2011, including arrests for theft, armed robbery and threats. He previously served five years in prison for armed robbery.

Authorities have not yet determined a motive for the latest attack.