HAYWARD (CBS SF) — Police are looking for the suspect in the assault of an elderly man knocked unconscious at a Hayward park during Labor Day weekend.

On Aug. 31 around 6:45 p.m., the 70-year-old man was collecting recyclables in the Pavillion picnic area of Kennedy Park where a group of about 10 to 20 men and women were having a party, police said.

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A woman from the group approached the elderly man and started a conversation with him, according to police.

A man from the group then approached the elderly man and punched him, knocking him down to the ground, police said.

The elderly man was left on the ground as the crowd continued their party until his wife found him an hour later, according to police.

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He suffered significant brain trauma that may be permanent, police said.

As of Thursday, the man is in critical condition and hadn’t regained consciousness, police said.

The suspect is described as a black man standing about 6 feet tall and weighing around 180 to 200 pounds.

Anyone with information on the assault is asked to call Hayward police at (510) 293-7034 or Inspector Rob Lampkin at (510) 293-7079.

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