Basler is also charged with attempted murder for allegedly wounding Joel Ross, who underwent emergency surgery after being stabbed behind E.T.'s Bar at 27423 Jefferson Ave. about 10:15 p.m. on Dec. 26.
Basler is additionally charged with preventing or dissuading a witness and assault with a deadly weapon to produce great bodily injury. Court papers indicate he has a "strike" from a felony robbery conviction dating back to 1998.
The judge granted prosecutor John Davis' request that Basler be held without bail and scheduled a Feb. 27 felony settlement conference.
According to witnesses, the stabbings were preceded by an argument inside the bar between Basler and Armstrong, who began fighting and continued the brawl in an alley outside the business, according to sheriff's investigators.
Basler allegedly left the scene, but returned a few minutes later in his truck accompanied by Marvin Black, 25, and James Wing Fung, 29, both of San Diego.
The three began brawling with Armstrong, Ross and another friend, Christopher Martin, according to sheriff's Detective James Peters.
A witness, identified as Ryan Brieda, told the detective that he spotted the "pocket clip of a knife on the front left pocket of Matthew Basler minutes before the stabbing," Peters wrote in an affidavit.
Another witness, who identified herself as Black's girlfriend, said Fung called her to warn her not to talk to police and she could hear Basler's voice in the background, also threatening her, according to the affidavit the Peters submitted to secure an arrest warrant.
That witness also told police that she had heard Fung say he had used his knife during the fight behind the bar and that he left it at the scene of the stabbing, Peters wrote.
Basler was identified by the witness, and police located him hiding in Vista on Jan. 11.
Black and Fung were arrested Dec. 29, and the charges against all three men were filed Jan. 5.
Wing has not yet been arraigned, and Black is awaiting a felony settlement conference.
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