A gunman has shot dead at least 12 children at a school in the Brazilian city of Rio de Janeiro before killing¹ himself, police say.

巴西城市里约热内卢警方称，一位男子闯入某学校，射杀至少12名儿童后自杀。

The gunman left a note saying he wanted to kill himself
At least 12 others were wounded when the man entered the school with two revolvers（左轮手枪） and began shooting.

The killer² has been identified as 23-year-old former pupil Wellington Menezes de Oliveira.

President Dilma Rousseff wept as she condemned³ the school massacre⁴（大屠杀，惨败） - the first of its kind in Brazil.

The attack happened at the Escola Municipal Tasso da Silveira school in the western Realengo area.

Officials said Oliveira arrived at the start of the school day and got into the building by saying he had come to give a lecture, but then went into a classroom and began shooting.

Teachers barricaded⁵ the doors of other classrooms while children hid under desks.

Some wounded children escaped and alerted police, who rushed to the scene.

'Asking forgiveness'

Police said the gunmen shot himself in the head after he was confronted by officers.

"The shooting was still going on when I arrived at the school," military police Sgt Marcio Alves told O Globo.

"I found him on the second floor coming out of a classroom. He pointed⁶ his gun in my direction, he got shot and fell, and immediately committed suicide."

Officers said the fast response had prevented an even bigger massacre at the school of around 400 pupils.

"If the police did not arrive as quickly as they did the tragedy could have been far worse, because this man had a lot of ammunition⁷（弹药） and was carrying two guns," police Col Djalma Beltrame said.

Police said they found a rambling⁸（漫步的，闲聊的） letter on his body which showed he was on a suicide mission.

The letter reportedly gave detailed⁹ instructions on how his body should be prepared for burial beside his adopted mother.

It asks that "his tomb be visited by a loyal follower¹⁰ of God to pray before my burial asking God forgiveness for what I have done".

"Nothing that is impure¹¹（肮脏的） can touch my blood," it read.