Police in Taichung have widened a probe into a July shooting at an office building, arresting five more people and seizing drugs — a sign the case runs deeper than one gunman.

• A man with gang ties fired 13 shots at the ground-floor entrance of a Taichung office building in July after a drunken argument, then turned himself in. No one was hurt.
• Investigators say friends helped him get the gun in Miaoli before he returned alone to carry out the shooting.
• Searches in late July netted five accomplices, along with phones and marijuana. Two suspects are being held without visitation, and a minor has been placed in juvenile detention.
• The building housed a private members' club where the drinking dispute started, and police are now checking whether businesses there were operating illegally.

Outlook: Prosecutors in Taichung will pursue weapons and drug charges while police keep sweeping office buildings for fraud, gambling, and money-laundering fronts.