A massive explosion hit Egyptian police headquarters in downtown Cairo Friday. A car bomb tore through the site around dawn killing four people and wounding 76, according to the state news agency MENA.

According to USA Today, Friday’s bombing is the deadliest bombing in Egypt since a military coup ousted Islamist President Muhammad Morsi last summer.

The explosion caused damage to the police headquarters including strips of the facade and windows. After the explosion smoke could be seen above the capital and shortly after another bombing occurred. The second attack was smaller and caused by a homemade bomb that exploded across the Nile River.

According to the BBC, the explosion occurred in the Dokki district of the capital and resulted in another death and 15 others being wounded. Reports stated that police vehicles were targeted near the metro station.

Friday’s attack comes just a day before the three-year anniversary of the uprising against Hosni Mubarak, Egypt’s former president. Mubarak was the president of Egypt for 30 years before citizens began to protest against his reign. In 2011, hundreds of thousands took to the streets to protest against him.

Earlier this week, Egypt’s interim President Adly Mansour spoke at Cairo’s Police Academy and assured the public that something will be done to deal with terrorism plaguing the community, USA Today reported.

As the attacks continue there has been a need to inform travels and American residents to be extra cautious. A security message for U.S. citizens read: “U.S. citizens are advised to elevate their level of awareness as we move into the weekend and limit their movements on Saturday, January 25 to the near vicinity of their neighborhoods.”