Updated

The chief operating officer of the National Children's Museum in Washington was arrested Tuesday on child pornography charges, accused of using his work computer to send explicit images to others — including an undercover New York City detective.

Robert A. Singer, 49, was arrested at his home in Falls Church, Va., on charges that he sent the pornographic images to a detective posing as a 33-year-old mother and her 12-year-old daughter, U.S. Attorney Michael Garcia said.

Singer was identified in the criminal complaint as a spokesman for the Capital Children's Museum, which closed in September 2004 to prepare for renovations. The museum, which plans to reopen in 2012 as the National Children's Museum, said in a statement that officials were "horrified" by the events.

The complaint filed in Manhattan federal court said Singer used the screen name Badboy2at to initiate contact with the detective in a chat room. Singer sent the detective about 80 explicit images of child pornography from his work and home computers, the complaint said.

The images sent from Singer's museum computer depicted sexual acts between minors and adults, the complaint said. Singer also sent the daughter two images with instructions to "just delete it when you are done."

Singer also exchanged images with other people while sending the pornography to the detective in August and September, the complaint said.

Singer was charged with five counts of distributing child pornography in interstate commerce. He was detained Tuesday pending a bail hearing later in the week. If convicted, he could face a prison term of up to 40 years on the most serious charges.

A man who answered the phone at Singer's residence Tuesday said that there was no one to immediately comment on the arrest and that it was not clear who his lawyer might be. Later in the day, a message left at the number for comment was not immediately returned.

The complaint also accused Singer of boasting in his e-mail communications that he worked near "all your favorite" monuments.

The museum's offices are a mile from the Washington monument, a mile and a half from the White House and a little over a mile from the Capitol, the complaint said.

The museum said in its statement it would fully cooperate with law enforcement and had suspended Singer and barred him from the property.

"Anyone who does anything that might endanger the welfare of a child has no place here," it said. "Harming children is against everything we stand for as an organization and as individuals."