NEWARK, N.J. (AP) — New Jersey authorities said Wednesday they’re working with federal officials to determine how widespread lead in Newark’s drinking water might be, as the city handed out bottled water to residents for the third day in a row.

New Jersey Gov. Phil Murphy, Department of Environmental Protection Commissioner Catherine McCabe and Newark Mayor Ras Baraka spoke at a news conference after touring a bottled water distribution center.

The event came just days after word that two homes in New Jersey’s biggest city tested positive for lead in the water despite the use of filters, and the mayor and governor vowed to hand out bottled water.

McCabe said she is meeting in Washington Thursday with federal Environmental Protection Agency Administrator Andrew Wheeler about the issue, and she added that officials are trying to get a handle on how widespread the issue is. She emphasized that authorities have limited results so far.

Newark dealt with elevated lead levels in its service lines for years and distributed nearly 40,000 filters since last year because some homes with lead service lines tested positive for the substance.

The latest issue came about when three homes’ filters were checked recently and two tested positive for lead.

Officials say no level of lead is safe. But federal rules set a level of 15 parts per billion as a tripwire. In Newark’s case, authorities said the lead is leaching in from the pipes and is not originating from the source water, which comes from a water treatment plant about 18 miles northwest of the city.

It’s unclear how high the lead levels in the two homes that tested positive were. McCabe and Murphy stressed Wednesday that the levels showed a drop but weren’t low enough to meet the federal threshold. Baraka said the city doesn’t yet have enough information to know whether the filters the city distributed are working. McCabe noted that the same filters have been used in Flint, Michigan, where lead leached into the water supply in 2014 and 2015.

Newark operates a lead information website that allows residents to look up whether their homes have lead service lines.

Murphy said the state has about 70,000 cases of water through its emergency management agency available. He added that private corporations and faith-based groups are also volunteering water to give to residents.