West African hotels from Dakar to N'Djamena are strengthening security, adding armed guards and increasing cooperation with local authorities as a pair of high-profile attacks have exposed a growing Islamist threat to foreign travelers.

Al Qaeda fighters killed 30 people on Friday at a hotel and restaurant in Ouagadougou, the capital of Burkina Faso. The assault, the country's first militant attack on such a scale, came just two months after Islamist militants killed 20 people at a Radisson hotel in Mali's capital Bamako.

In both instances the attacks targeted establishments popular with Westerners, dozens of whom were taken hostage. Witnesses to the Ouagadougou attack spoke of gunmen singling out white foreigners for execution.

High-end hotels in major cities across the region have been quick to react in the wake of the violence, which diplomats and analysts warn likely marks a new strategy by al Qaeda in the Islamic Maghreb and its allies.

Abidjan and Dakar, the largest cities in Ivory Coast and Dakar, are viewed as particularly attractive to Islamist militants due to their large Western expatriate populations and steady flow of tourists and business travelers.

"If you strike the capital, you are seen to be striking harder and the threat is there for other cities like Dakar and Abidjan," Cynthia Ohayon, West Africa analyst at International Crisis Group, said by phone from Ouagadougu.

But diplomats said they had no information on specific threats in either city.

At the Sofitel Hotel Ivoire, one of Ivory Coast's most luxurious hotels, uniformed police officers were posted around the grounds. The use of metal detectors and body searches was being ramped up. Guard dogs were used to help patrol the lobby.

The 358-room luxury hotel is regularly fully booked as Ivory Coast's booming economy draws investors and business people from around the world. It also plays host to large international meetings at its adjoining conference center.

"Since the beginning of the week, the security measures have been reinforced," said Alfred Kouassi, a hotel employee working in the lobby. "The police often come to speak to us with us."

In Senegal, gendarmes have been deployed at roundabouts and on major streets in neighborhoods popular with Westerners.

Dakar's Radisson Blu, the sister hotel of the establishment attacked in Bamako in November, installed additional cameras inside and outside, ordered vehicle barriers and had increased security personnel well before the Ouagadougou attacks.

"Of course, there is always a risk, but I can assure you that we have in place all the precautions to control the building in the most professional way," said Jorgen Jorgensen, the hotel's general manager.

In Chad's capital N'Djamena, which was hit by deadly attacks by Islamists in June and July, the government has called upon hotels to carry out car and body searches as well as increase their collaboration with local authorities.

TOURISM THREATENED

While tourism to the region has long been hobbled by poor infrastructure and expensive air travel, it had recently seemed that change was in the air.

Low-budget airlines have launched or expanded in the continent. West Africa had 13,500 hotel rooms in development in 2014, a third of the continent's total.

Senegal - one of three countries in the region, along with Nigeria and Ghana, that had surpassed 1 million international arrivals - aims to triple tourists by 2025.

Ivory Coast had the third-largest growth of visitor arrivals in Africa in 2014, according to the African Development Bank.

But suddenly the outlook looks much less rosy.

Even in Senegal, long considered to be a bulwark of stability, France has urged citizens to avoid public locations including nightclubs and stadiums.

At the Hotel du Phare, a budget hotel in Dakar that hosts weekly parties popular among twenty-something expatriates, bag checks and security guards for their soirees had increased and secondary doors had been closed.

Penelope Theodosis, who manages the hotel along with her husband, said she had a guard stationed outside at night, but added that she was walking a fine line between making her guests feel safe and frightening them.

"We only have nine rooms ... A guardian inside the hotel would cause more fear than reassurance."