Investigators said today that tests indicate the presence of hydrogen sulfide in the manhole that claimed two lives on Monday.

Experts say that the levels of the gas were low at the time of testing, but they caution that levels can go from dangerous levels to low levels very quickly.

Click "NEXT" below your video player for parents worries about hydrogen sulfide and a nearby daycare center.

Michael Blau, Tarrytown Village administrator, said that Anthony Ruggiero, the first man in the well, didn?t take an air quality monitor with him when he went into the manhole and that John Kelly, the volunteer firefighter who went after Ruggiero, wasn?t wearing a breathing apparatus when he entered the manhole.

An autopsy conducted yesterday turned out inconclusive and officials said more test will be needed. State labor officials are also continuing their investigation.

Wake services for Ruggiero begin today at the Coffey Funeral Home in Tarrytown from 7 to 9 p.m. and will continue tomorrow from 2 to 4 p.m. and from 7 to 9 p.m.

Wake services for Kelly begin tomorrow from 3 to 9 p.m., also at the Coffey Funeral Home. A special service for firefighters and medics will be held at 7:30 p.m.

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