Investigators are trying to determine if return gunfire from police, not a self-inflicted gunshot, killed a man who shot his girlfriend, according to The Eagle-Tribune.
Authorities had previously said Yenny Santos of Lawrence, Massachusetts, was shot by Antonio Gonzalez before he took his own life.
Gonzalez shot Santos in April, prompting a police standoff.
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The paper reports Gonzalez smashed out a third-floor window and fired at officers, before police immediately returned gunfire.
Santos remains hospitalized.