A lead poisoning scandal has struck a second US town, with schools closed Monday in Sebring, Ohio, and the water treatment plant operator accused of falsifying reports.

Elevated lead levels were detected months ago but local officials failed to warn residents until last week despite pressure from the Ohio Environmental Protection Agency. Some 8,100 people rely on the Sebring water system.

The agency said it has "reason to suspect that the operator falsified reports" and has asked the federal Environmental Protection Agency's criminal division for help with the investigation.

The Ohio case comes as a special prosecutor was appointed to investigate how the city of Flint, Michigan, exposed 100,000 residents to lead poisoning after cutting water treatment costs.

Officials are accused of ignoring months of health warnings about foul-smelling water, even as residents complained it was making them sick.

President Barack Obama weighed in on the Flint crisis last week, saying he would be beside himself if the health of his children had been placed at risk in such a way.

Lead exposure is harmful to everyone, but it can have devastating impacts on young children by irreversibly harming brain development. It has been shown to lower intelligence, stunt growth and lead to aggressive and anti-social behavior.

- 'Do the right thing' -

A spokeswoman for the Ohio Environmental Protection Agency said she could not release further details about what types of reports were allegedly falsified or speculate as to why Sebring officials failed to warn the public.

"We were working with them for quite a while trying to get information out of them and get them to do the right thing," Heidi Griesmer told AFP.

"The games the village of Sebring was playing -- they gave us incomplete data time and time again, and were not providing documents when they were due," she said.

"It made it difficult for our field office to determine whether or not they notified their customers."

The agency is still trying to piece together exactly what happened.

It appears as though the problem was detected when the local OEPA field office was reviewing Sebring's routine testing reports, Griesmer said. Those tests found elevated lead levels in six houses.

Rather than immediately implementing corrosion control strategies, the local plant operator wanted to keep taking more samples to see if he could get an average lead level low enough to avoid action, according to a September 25 e-mail released by the OEPA.

The state agency eventually issued its own warning on December 3 about lead contamination in the Sebring water supply but most people in town did not hear about it until last week.

That's when the agency's director stepped in.

The schools were closed for testing, the county's public health department issued an advisory and village officials were given a formal notice of violation.

Pregnant women and children were asked to have their blood tested for elevated lead levels at a free clinic on Sunday and officials also began distributing bottled water and filtration systems.

- Water treatment working? -

"It has become apparent that our field office was too patient in dealing with the village of Sebring's 'cat and mouse' game and should have had closer scrutiny on the water system meeting its deadlines," Ohio EPA Director Craig Butler said late Sunday.

"We are in the process of developing new protocols and appropriate personnel actions to ensure that our field staff takes action when it appears that a water system is not complying and taking their review seriously."

The OPEA eventually convinced officials to alter their water treatment in order to reduce the water's acidity and decrease the chances that lead would leach out of old pipes.

The treatment appears to be working, Griesmer said: follow-up tests found that four of the six houses with high lead levels are now below the danger zone.

However, additional tests detected elevated lead level in water from a drinking fountain in one of the town's schools and at least three homes also have lead in their water.

Schools remained closed Monday. The OEPA issued an emergency order Monday removing the head of the water treatment plant and requiring the plant to comply with state rules.

Ohio Governor John Kasich's office issued a statement saying he was "encouraged to learn of the improving water situation" and supported the Ohio EPA's work to force Sebring "to get serious about taking corrective action."

The contaminated water advisory will not be lifted until Sebring achieves two rounds of lead-free sampling in consecutive six month periods.