A blast rocked the office of the lawyer Sakhr al-Hashem in Furn el-Chebbak on Monday afternoon, causing material damage.
The lawyer, who was at the office at the time of the incident, escaped unharmed along with his two sons who work with him.
TV footage showed several parts of the office largely destroyed.
Speaking to a-Jadeed TV, al-Hashem said it is unlikely that the explosion was caused by gas or electricity.
The lawyer is known for handling controversial cases and he is the counsel of one of the detainees in the case of the Beirut port blast.
In his remarks to al-Jadeed, al-Hashem hoped the incident is not a “message,” describing the explosion at his office as “very, very, very violent.”
MTV meanwhile reported that the blast was caused by an electric “water heater.”