The U.S. Embassy in Kabul warned American citizens in Afghanistan on Monday that officials had received “credible reports of an imminent attack,” and urged them to be careful when traveling in the area.

The embassy said in a statement that the reports indicated that an attack could happen in the capital “within the next 48 hours.”

“During this period of heightened threat, the U.S. Embassy strongly urges U.S. citizens to exercise extreme caution if moving around the city,” the embassy said in the release. It added that there were no further details regarding the targets, timing or method of the planned attack.”

In accordance with the Travel Warning for Afghanistan, the Department of State continues to warn U.S. citizens against travel to Afghanistan. The security situation in Afghanistan is extremely unstable, and the threat to all U.S. citizens in Afghanistan remains critical. U.S. citizens currently visiting or residing in Afghanistan may wish to consider departing. The Embassy strongly urges U.S. citizens who decide to remain in Afghanistan to review your personal security plans, take appropriate steps to enhance your personal safety, remain aware of your surroundings, monitor local media for updates, and maintain a high level of vigilance.

Sediq Sediqqi, spokesman with the Afghan interior ministry, told NBC News that such reports were fairly common, though Sediqqi also told the network that they are taken “very seriously.”

The embassy’s statement — titled “Emergency Message for U.S. Citizens” — was issued just days after a suicide bomber struck in Kabul, leaving one dead and one wounded, according to the Associated Press.

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