By John Krinjak

Email: jkrinjak@abc6.com

Twitter: @johnkrinjakABC6 

BARNSTABLE, Mass. (WLNE) -- 29-year-old Thomas Latanowich went before a judge Friday, charged with the murder of 32-year-old Yarmouth Police Officer Sean Gannon.

Latanowich is charged with shooting and killing Gannon, while he and other officers were trying to arrest Latanowich on a warrant at his home Thursday.

Dozens of fellow police officers packed that courtroom as Latanowich was arraigned.

The judge entered a not guilty pleas on his behalf on that murder charge, as well as a charge of mistreating or interfering with a police dog.

Latanowich was ordered held without bail.

He showed very little emotion in the courtroom, holding his head down the entire time.

And following this court appearance we're learning much more about Latanowich's extremely lengthy criminal history, which includes 111 separate charges.

Officer Gannon was at Latanowich's house yesterday, because he had a new warrant out for his arrest--after missing a drug test while out on probation.

In 2010 he was sentenced to four to five years in prison for assault with a dangerous weapon and other gun charges.

He's also been convicted on drug charges and witness intimidation.

Latanowich was released on parole in 2013...before going back to jail in 2014 for violating his probation.

Latanowich's next court date in this case is a probable cause hearing on June 26th.

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