(Christopher Robbins) Nine motorcyclists, including an off-duty undercover NYPD officer, have been arrested for their involvement in the road rage incident that ended in the vicious beating of driver Alexander Lien. Now the Post reports that police are looking to arrest four more people connected to the incident.

The Post's police sources tell the tabloid that the department is "pulling out all the stops" to identify the makes and models of the suspects' motorcycles. Three of the machines have around 300 registered owners apiece. “They are in the beginning stages of going to every address to see what they can learn,” a source says.

Read More: Gothamist

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