WASHINGTON (CBSDC/AP) — A new report released by the Pentagon inspector general finds that felons have routine access to military bases throughout the nation.

According to CBS News, the report finds that 52 felons had access to military installations which put “military personnel dependents, civilians, and installations at an increased security risk.” The felons had access to these bases ranging from 62 to 1,035 days.

CBS News special correspondent John Miller reports that the felons who received access included “drug dealers” and “alleged child molesters.”

The Defense Department Inspector General found that one of the Navy’s security programs, which is more often used to review contractors who do not require security clearances, did not vet the workers well enough to eliminate the risks of allowing them access to Navy facilities.

The report states that the Navy Contractor Access Control System did “not effectively mitigate access control risks,” according to CBS News.

Armed and with a “secret” level security clearance, Navy contractor Aaron Alexis was able to enter the Washington Navy Yard and swipe an access card to get into the headquarters building where he shot and killed 12 people and wounded several others.

Although that system was not the one used to evaluate Alexis, the 34-year-old information technology worker involved in the shooting, it underscores persistent problems with the screening processes.

Those worries prompted Navy Secretary Ray Mabus to order two security reviews Tuesday and the plans for Secretary of Defense Chuck Hagel to order a review of physical security and access at all department installations worldwide.

Rear Adm. John Kirby, a Navy spokesman, said officials are in the process of reviewing the IG report, “but it does not appear that the findings of the report could have in any way prevented the shootings yesterday.”

Alexis, a former Navy reservist, was put through a more extensive, detailed security review process in order to get his “secret” level clearance — that he had while in the military and then later for his contracting job.

The federal government investigated Alexis in 2007 and he was given his security clearance in March of 2008, a defense official said. Alexis got a clearance to handle “secret” information, a level that is good for 10 years before it has to be renewed.

Alexis told Rhode Island authorities last month that he was hearing voices harassing him and wanting to harm him through a wall at the hotel he was staying.

On Aug. 7, police alerted officials at the Newport Naval Station about the naval defense contractor’s call. But officers didn’t hear from him again.

By Aug. 25, Alexis had left the state. He arrived in the Washington area, continuing his work as an information technology employee for a defense-related computer company. Again, he spent nights in different hotels. He suffered from serious mental problems, including paranoia and a sleep disorder, and was undergoing treatment from the Department of Veterans Affairs, according to the law enforcement officials.

But Alexis wasn’t stripped of his security clearance, and he kept working.

According to Navy officials, the reviews ordered by Mabus will take two tracks. The first one is due by the beginning of October and will be a quick assessment of security at Navy bases around the world. The second one will be longer and more detailed, and will look at how well the Navy protects its installations and screens its personnel.

Rep. Mike Turner, R-Ohio, said that the IG report raises serious concerns about access to military installations, including whether felons may have been able to gain access to some bases due to insufficient background checks.

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