A group of Brazilian senators who went to Venezuela to meet with jailed opposition politicians didn't make it far past the airport.

The group headed by Brazilian opposition leader and former presidential candidate Aecio Neves landed at a coastal airport Thursday, but turned back before making it to Caracas, citing congestion and a protest. The drive usually takes an hour.

Venezuelan hardline opposition leader Maria Corina Machado said maintenance work snarled traffic and pro-government protesters surrounded the lawmakers' bus in a threatening way.

The group wanted to visit imprisoned ex-mayor Leopoldo Lopez, among others.

After the lawmakers headed back home, the Brazilian Foreign Ministry released a statement saying hostile acts against its politicians are unacceptable and promising to seek an explanation from the Venezuelan government.