The FBI allocates only about $500,000 of its $11 billion budget for counter-drone capabilities, a senior bureau official told House lawmakers Tuesday, who heard the agency still has not determined who is responsible for a series of drone incursions in New Jersey.

Robert Wheeler Jr., the assistant director of the Critical Incident Response Group in the FBI, faced difficult questions about the incursions, which started last month, during a joint hearing by the Subcommittee on Counterterrorism, Law Enforcement, and Intelligence and Subcommittee on Transportation and Maritime Security.