The missiles shattered glass in the guard post and cracked fibreglass-like material in the gate.
More than 200 white-clad members of Indonesia's militant Islamic Defenders Front (FPI) were protesting over Danish cartoons lampooning the Prophet as well as his depiction in a sculpture at the US Supreme Court in Washington.
About 50 police were on hand but unable to keep the protesters away from the gate, witnesses said.
Maksuni, an FPI deputy leader, told reporters after the protests: "This is not the last warning. This is only the beginning. There will be bigger actions against them."
"Suicide bombings! Prepare for a bomb", said one protester.
Weeks of sometimes violent protests by Muslims across the world against the cartoons, first published in Denmark and then by many European newspapers, have triggered fears of a clash of civilisations between the West and Islam. Many Muslims believe that it is blasphemous to publish images of the Prophet.
An embassy statement read to Reuters by a spokesman said the US government deplored the violence, adding:
"Ambassador B. Lynn Pascoe said that this was a pre-meditated event that was staged for television by a small group which seeks to disrupt the relationship between the United States and Indonesia by inflaming popular opinion."
"This sort of thuggery is unacceptable and needs to be treated as what it is."
The statement said that the United States shared Indonesian President Susilo Bambang Yudhoyono's view "that the cartoon issue should not be used as a wedge between cultures".
Yudhoyono, other officials, and leaders of moderate Muslim groups in Indonesia, the world's most populous Muslim nation, have condemned the cartoons while urging that protests against them be peaceful.
The Mohammad depiction at the US Supreme Court that was an added issue in the latest protest is one of a number showing historical figures viewed as lawgivers and sculpted in the 1930s.Last Mod: 20 Eylül 2018, 18:16