As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED AND THE AIRCRAFT RETURNED TO LGA DUE LOUD SQUEAL FROM CAPTAINÏ¿½S #2 WINDOW. THE AIRCRAFT LANDED SAFELY AT LGA WITHOUT FURTHER INCIDENT. MAINTENANCE FOUND #2 WINDOW DRAIN TUBE DETERIORATED. REPAIRED DRAIN TUBE PER AARD 25-11-00-4.