NAIROBI, Kenya — The U.S. State Department issued a warning against travel to Kenya after al-Qaida-linked gunmen stormed a shopping mall in the capital Nairobi in an attack, killing at least 67 Kenyans and foreigners.

“U.S. citizens in Kenya, and those considering travel to Kenya, should evaluate their personal security situation in light of continuing and recently heightened threats from terrorism and the high rate of violent crime in some areas,” the State Department said in an e-mailed advisory Saturday.

On Sunday, Kenyan officials responded by asking the U.S. government to lift the advisory, calling it "unnecessary" and "unfriendly.”

Islamist militants attacked Nairobi’s Westgate mall on Sept. 21, spraying automatic gunfire, hurling grenades and seizing hostages. Five U.S. citizens were among those injured, according to the State Department.

The advisory also cited incidents involving gunfire and grenades in Kenya’s North Eastern Province over the past 18 months and said U.S. embassy staff are prohibited from travel to several northeastern cities including El Wak, Wajir and Liboi.

Kenyan President Uhuru Kenyatta asked countries on Sept. 22 not to announce travel advisories against visits to the East African country. The country’s tourism industry, which accounts for 12.5 percent of gross domestic product, may see an impact from the four-day attack on Nairobi’s upscale shopping complex, according to Moody’s Investors Service. Tourism generates the most foreign exchange for Kenya after tea exports.

“There are no restrictions on U.S. embassy employee travel to Kenya’s most popular tourist destinations such as Masai Mara, Amboseli, Lake Nakuru, Tsavo, Lamu Island, Hell’s Gate, Samburu, Mount Kenya, Malindi, and Nairobi,” the State Department said.

The Kenyan economy was “unshaken” after the attack, National Treasury Secretary Henry Rotich said yesterday in an e- mailed statement.

“Tourism might be affected badly in the short term,” Bob Collymore, chief executive officer of Safaricom Ltd., Kenya’s biggest company by market value, said in an interview in Nairobi yesterday. “But we don’t see a long-term knock on the economy.”