As police searched for him, and as he lay bleeding in his boat hideout, Boston Marathon bombing suspect Dzhokhar Tsarnaev wrote "F*** America" on the side panel of the boat, police in Massachusetts told ABC News.
Officers said they also discovered the phrase "Praise Allah" on the boat's side panels and several anti-American screeds, including references to Iraq, Afghanistan and "the infidels."
A Massachusetts official showed ABC News what he said was a cell phone picture of the phrase "Praise Allah," written in black ink, with a bullet hole above it, believed to have been written by Dzhokhar as he hid inside the boat in Watertown, Mass.
Also seen in the picture was the faintly written word "brother," which the official said was part of a reference by the younger Tsarnaev "that was something about his brother is lucky to be with Allah first."
Tamerlan Tsarnaev was killed hours earlier during a shootout with police several blocks away from the location of the boat.
Spokespeople for the Massachusetts State Police and the Watertown police had denied the existence of the writings when first asked about them by ABC News two weeks ago.
Today, both departments referred reporters to the FBI. A federal law enforcement official confirmed reports first broadcast by CBS News that writings had been discovered inside the boat.
The discovery of writings intensified tensions between the FBI and local police when FBI agents believed some Boston officers and state police had taken cell phone pictures of the writing.
Agents demanded the phones of all officers at the scene the night of the capture of Dzhokhar be confiscated to avoid the photos becoming public before being used as evidence at trial, according to two law enforcement officials.
A FBI spokesperson said agents cannot confiscate phones without a warrant and officials said none of the police approached would agree to turn over their phones to the FBI.
Dhzokhar and Tamerlan Tsarnaev are accused of setting off a pair of bombs near the finish line of the Boston Marathon April 15, killing three people, including an eight-year-old boy, and injuring more than 260 others. Tamerlan was killed in a shootout with police days after the attack, while Dhzokhar was wounded and later captured in the boat.