Unknown assailants threw a grenade at a cafe in Lebanon Wednesday, just days after warnings had circulated to restaurants against staying open during the Muslim holy month of Ramadan.

Four people were wounded after two men on a motorcycle threw the explosive device at the Makiya cafe in Tripoli, Lebanon, and then sped off, Middle East news site Al Arabiya reported Thursday.

No claim of responsibility was issued, but locals suspect the attack was prompted by the food establishment being open during the daylight fasting hours.

“The cafe sells coffee during the day in Ramadan, when most residents are fasting,” a Lebanese security official told Agence France-Presse.

Plates of food are prepared and ready for free distribution for the Iftar meal that breaks the day's fast at sunset, during the holy month of Ramadan outside a mosque in Islamabad, Pakistan, Monday, June 30, 2014. Muslims throughout the world are marking Ramadan--a month of fasting during which observant Muslims abstain from food, drink and other pleasures from sunrise to sunset. Ramadan is meant to be a time of reflection and worship, remembering the hardships of others and being charitable. (AP Photo/Anjum Naveed)

Plates of food are prepared and ready for free distribution for the Iftar meal that breaks the day’s fast at sunset, during the holy month of Ramadan outside a mosque in Islamabad, Pakistan, Monday, June 30, 2014. Muslims throughout the world are marking Ramadan–a month of fasting during which observant Muslims abstain from food, drink and other pleasures from sunrise to sunset. Ramadan is meant to be a time of reflection and worship, remembering the hardships of others and being charitable. (AP Photo/Anjum Naveed)

Restaurants have been warned in recent days about staying open during Ramadan, even though 5 percent of Tripoli’s population is Christian.

According to AFP, a social media message went around Lebanon’s second-largest city about restaurants that remain open, saying, “these pigs are selling food and drink during the day and in view of everyone.”

The message told residents “to deal with them in an appropriate manner,” without specifying how.

Tripoli Mayor Nader Ghazal had asked eateries to “respect the sanctity of the holy month of Ramadan” and urged residents of the city to refrain from eating in public. His call sparked a backlash from some who viewed it as an assault on their freedom, though the mayor said his request was voluntary.

“There is no law prohibiting it,” Ghazal said of eating in public, according to Al Arabiya.

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