HOUSTON, Dec. 19 -- Health officials confirmed the second case of H1N1 virus in a Texas hospital Thursday, one day after they confirmed the first case there, local media reported.

Officials said Thursday one of the eight patients who were treated for the same "mysterious" flu-like illness at a medical center in Montgomery County in southeast Texas tested positive for H1N1, the website of the Houston Chronicle reported.

On Wednesday, officials said another of the eight patients had H1N1. Four of them have already died as of Wednesday.

Two others who are alive have tested negative for flu. Montgomery County Public Health District spokeswoman Jennifer Nichols-Contella said in a written statement Thursday that tests are to be continued on the two.

The eight patients, ranging in age from 41 to 68, were admitted to the hospital with similar flu-like symptoms. No details were available Thursday on the dates of the deaths or hospitalizations.

Meanwhile, local media KHOU.com, quoting unnamed sources, said H1N1 has already killed six people and left 14 critically ill in the Greater Houston area recently. The toll cannot be verfied immediately.

Spokeswoman for the Texas Department of State Health Services, Christine Mann, said Thursday her agency is aware of suspected flu cases that Montgomery County public health officials are investigating. She said the county is sending specimens to the Centers for Disease Control and Prevention for more extensive testing and confirmation.

"We'll wait and see what they find," Mann said, adding that the H1N1 virus, formerly known as swine flu, is the predominant strain this season, which started in September and typically runs until spring.

Official said the virus is the same strain of H1N1 that caused a pandemic in 2009. Doctors have been seeing hundreds of new flu cases recently in Texas and nationwide. During the week ending Dec. 7, at least four U.S. states -- Texas, Louisiana, Alabama and Mississippi -- reported high levels of influenza-like illness.

The illnesses started with flu-like symptoms, then progressed to pneumonia and, in some cases, organ failure. The flu pandemic in the United States began in the spring of 2009. The virus had spread to the U.S. from an outbreak in Mexico. As of mid-March 2010, the U.S. Centers for Disease Control and Prevention estimated that about 59 million Americans contracted the H1N1 virus, 265,000 were hospitalized as a result, and 12,000 died.