AUGUSTA, Maine — In perhaps a sign of the times, the “Open for Business” highway sign that symbolized the LePage administration’s pro-business agenda may have become a casualty of Maine’s increasingly caustic political atmosphere.

The blue highway sign that Gov. Paul LePage ceremonially placed on Interstate 95 in Kittery, just inside the Maine’s border, disappeared sometime during the past week. And the Maine Department of Transportation has no idea where it went.

“It has been removed and we did not remove it,” said Mark Latti, a DOT spokesman. “We alerted the governor’s office and reported it to the state police.”

The theft first was reported Wednesday by WCSH-6 in Portland. In fact, DOT staff were unaware of the sign’s disappearance until contacted by journalists from the television station inquiring whether the department had taken it down.

The oversized sign was presented to LePage on the night of his inauguration as a gift from supporters inspired by his campaign pledge to erect an “Open for Business” sign on I-95 if elected to the Blaine House. A group of supporters raised an estimated $1,300 to purchase the sign from a company that makes highway placards.

But the sign also has become a symbol for LePage’s critics of what they say is an administration intent on rolling back widely supported environmental and labor regulations.

LePage spokeswoman Adrienne Bennett said the sign’s theft was disappointing.

“Whether or not the sign is up, we are open for business,” Bennett said Wednesday afternoon. “It’s unfortunate that some person or persons decided to take it upon themselves to take the sign down.”

Asked whether the administration would replace the missing sign, Bennett replied: “We have no intention of using taxpayer dollars to put up another sign. What we would like to see is this sign put back.”

Bennett pointed out it was no easy feat for the thieves to remove the sign and would have required a ladder, tools to remove the bolts and likely a pickup truck to haul away the large sign.

LePage’s critics have accused him of effectively stealing a labor-themed mural from the Department of Labor building in Augusta. The administration removed the 11-panel mural earlier this year after receiving anonymous complaints that the images of workers, union strikes and prominent labor figures were too one-sided for a department charged with working with both employers and employees.

That decision sparked several weeks of protests from organized labor groups and artists and a warning from the federal government that Maine would have to pay back a grant that helped pay for the mural unless the artwork was re-displayed. The mural remains secluded in an undisclosed location, pending a decision about its future home.

In the case of the “Open for Business” sign, however, the parties who illegally removed the sign could face felony theft charges — punishable by up to five years in prison and a $5,000 fine — because it is valued at more than $1,000.