An online dispute between two Merrick teenagers resulted in a stabbing that left the victim in serious condition, authorities say. 

Prosecutors say Anthony Vas, 17, stabbed another 17-year-old who had come to his home to confront him about posts on Instagram. 

"An altercation quickly ensued at which time Vas stabbed the victim on the right side of his chest," says Detective Lt. Richard LeBrun. 

In court, Vas' attorney said the victim had been harassing his client for a while on Instagram.

"This is a good kid that was in some way challenged at his own home," says Guy Allen.

Allen did not elaborate on the nature of the alleged threats posed by the victim. 

Vas' father, Larry, says the alleged Instagram threats started with a dispute over a young girl and boiled over Wednesday when the victim came to their house. He says the 17-year-old physically provoked Anthony in the driveway before he was stabbed. He adds that it was all caught on a security camera.

Friends of the victim tell News 12 Long Island that the incident was a misunderstanding that should never have resulted in violence. 

Vas is facing felony assault and weapons charges. If found guilty, he could face a 25-year sentence. He was ordered held on $75,000.