Terrifying clip shows infamous serial killer Richard Ramirez's eerie response when asked why he killed people

Warning: This article contains discussion of sexual assault which some readers may find distressing.

A chilling clip of infamous serial killer Richard Ramirez captures his eerie response when asked about his reasons for killing at least 13 people under the moniker 'The Night Stalker'.

In the early 1980s, residents of Los Angeles were living in fear as more and more murders came to light throughout April 1984 to August 1985.

Prior to being caught, Ramirez would sneak into people's homes through open windows and unlocked doors and proceeded to take the lives of those inside.

When he wasn't on his murder spree, the criminal would rob and beat his victims, as well as carrying out sexual assaults.

The serial killer was finally captured on August 31,1985, and in September 1989 he found guilty of 43 counts, including 13 counts of murder, five attempted murders, 11 sexual assaults and 14 burglaries.

Ramirez was arrested after more than a year of crimes (Getty Images)

What was Richard Ramirez's motive?

The randomness of The Night Stalker's crimes confused police - a factor which helped him evade capture for so many months. His victims included a 60-year-old grandmother, a married couple, a 22-year-old woman and a 16-year-old girl, with heritages including white, Asian and Latino.

At his first court appearance, Ramirez yelled 'Hail Satan', and was seen with a pentagram on his hand.

However, when asked exactly why he killed his victims, Ramirez wasn't entirely open about his reasoning.

The killer gave a chilling response as a smile spread across his face at the question of his motive, prompting him to cover his mouth with his hand.

In footage obtained by Inside Edition, he then said: "No comment, no comment, I cannot answer that at this time."

Meanwhile, authorities suggested Ramirez had one simple goal: to kill.

See the footage below:

How was Richard Ramirez caught?

The Night Stalker's killing spree began to reach its end on August 25, 1985, after a 13-year-old boy heard Ramirez outside his home. He woke up his parents, and the family managed to spot some of the license plate digits of the car he was driving.

He then broke into the home of another victim, Inez Erikson, and told her he was the Night Stalker.

Erikson was sexually assaulted by Ramirez, but she was able to give a description of her attacker to police.

When police found the car he had been driving, a single fingerprint matched that of Richard Ramirez.

Within a couple of days, Ramirez's mugshot was plastered over newspapers and a group of bystanders ambushed him while he was trying to carjack a vehicle. The group managed to pin down Ramirez until police arrived and put him behind bars.

Where is Richard Ramirez now?

Ramirez died in June 2013 after being transported to a California hospital with health complications.

If you've been affected by any of the issues in this article, you can contact The National Sexual Assault Hotline on 800.656.HOPE (4673), available 24/7. Or you can chat online via online.rainn.org