Police and forensic experts gather evidence at the scene of Friday's attack in Tunis.
CNN  — 

A policeman died Friday of his injuries after two suicide bombers attacked a security post near the US embassy in Tunisia, the country’s interior ministry said.

The bombings in the capital, Tunis, injured four other policemen and a civilian. The ministry blamed the attack on “terrorists.” Sufyan al-Sulaiti, a spokesman for the anti-terror judicial branch, said the two attackers used a large amount of explosives and that the motorcycle they were riding was rigged with explosives.

The State Department said one of the embassy’s locally employed staff was injured in the attack, but that “no Americans were reported to have been injured.”

“We are outraged by this attack and saddened to hear of reports of one fatality from Tunisia’s security services,” the spokesperson said. “We compliment the Tunisian security forces on their quick and effective response to the incident.”

The spokesperson said the State Department is working with local authorities to investigate and that no organization has claimed responsibility for the attack.

The US embassy tweeted a statement from US Ambassador Donald Blome that said: “We reaffirm our commitment to our longstanding friendship with Tunisia and our alliance with them against the scourge of terrorism.”

Tunisian President Qais Saeed visited the five surviving victims at the Internal Security Forces Hospital, state news said.

The US embassy sent a tweet earlier confirming an explosion in the area, adding: “Please avoid the area and monitor local media for updates.”

The 2011 Arab Spring began in Tunisia and the country’s transition to democracy has been marred by violence. The nation has experienced several serious terror attacks since the Arab Spring, including the 2015 gun attack on the resort town of Sousse that left 38 people dead. But most attacks have been lower-level assaults on open targets, like the police.

The country has struggled to contain the expansion of jihadists, with a significant number of nationals joining groups like ISIS and al Qaeda.

CNN’s Angela Dewan and Ivana Kottasová wrote from London, Jennifer Hansler contributed reporting.