TUNIS, Tunisia -- A security agent guarding the Brazilian Embassy in Tunisia was stabbed in the heart Monday and was hospitalized in critical condition, according to the Tunisian Interior Ministry.

The suspected assailant was shot in the leg by police and arrested, the ministry said in a statement. It said the agent was stabbed after he asked the suspect why he was outside the embassy.

The area, in a residential zone of the capital, Tunis, was cordoned off by police.

Ministry spokesperson Faker Bouzghaya said the security guard was wounded in the heart.

Bouzghaya said the suspect’s son told investigators that his father is a 53-year-old teacher who had suffered psychiatric troubles and had not been home for two days.

The spokesperson said the suspect was not known to Tunisian security services and that the attack did not appear to have terrorist motives. Tunisia has experienced some terrorist and other attacks in recent years.