Suspected mass shooter Robert Card may have been seeking ex-girlfriend

Still-at-large suspected Maine mass shooter Robert Card may have been targeting a former girlfriend during the murderous rampage – and the message he left behind was a ranting suicide note to his son, according to a report.

Card’s sister told investigators she believed he may have been looking for his ex when he shot up the Sparetime Recreation bowling alley and the Schemengees Bar and Grille, ABC News reported, citing sources.

Investigators are looking into the possibility that the mass shooting — which killed 18 people and left 13 others wounded — began as a domestic dispute, the sources said.

The ex-girlfriend was not identified, nor was the suspect’s ex-wife, whose divorce over irreconcilable differences was granted in 2007, ABC News also reported, citing court documents.

In 2013, the divorce order was amended to include shared parental rights and responsibilities for their then-minor child, whose primary residence was with his mom, the documents reportedly state.

Card’s son was also the intended recipient of the mystery note investigators discovered Thursday while executing a warrant at Card’s unkempt home in Bowdoin, according to the outlet.

ABC News’ sources described it as a suicide note that also contained rantings and personal information such as bank account details.

Federal, state, county and local authorities are still desperately trying to locate Card, who is suspected of opening fire with at least one rifle at the bar and bowling alley in Lewiston, which is about 15 miles from Bowdoin.

The manhunt has extended to Canada as authorities there issued an alert for the “armed and dangerous” trained marksman three days after 18 people were killed and 13 others injured, with three people still hospitalized in critical condition, authorities said.

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Maine Gov. Janet Mills promised to do whatever was needed to find Card and to “hold whoever is responsible for this atrocity accountable … and to seek full justice for the victims and their families.”