The attack took place in the enclave of Cabinda, where a separatist group has waged a three-decade long war against the government.
Gabriel Ameyi, the Togo Football Federation vice-president, said players Obilale Kossi and Serge Akakpo had been wounded in the attack.
The AP news agency reported that two team doctors and a journalist travelling with the squad had also been injured.
The attack comes just two days before the start of the 2010 Africa Cup of Nations, a pan-continental tournament, which is the continent's biggest football event.
The Togo team had been training in Congo and were travelling to Angola by bus ahead of their match against Ghana on Monday.
High profile players
"This is probably the worst thing that could have happened at the start of the South African World Cup year"
Keir Radnedge, football author
Karthi Gnanasegaram, Al Jazeera's sports correspondent in London, said some high profile players, including Emmanuel Adebayor, who plays for the English club, Manchester City, were in the Togo team.
"We have spoken to Manchester City. They have told us he is definitely safe and he is unharmed, but he is obviously shaken by what has happened in the last few hours," she said.
Antonio Bento Bembe, Angola's minister without porfolio who is in charge of Cabinda affairs, condemned the attack.
"This was an act of terrorism that is being dealt with as we speak," Bento Bembe told Reuters.
Keir Radnedge, a leading football author and a former editor of World Soccer magazine, told Al Jazeera that security arrangements in Angola had failed.
"The problem with any sports organisation is that they do rely on this moratorium that generally sports teams don't get attacked. Now obviously, that is something that is falling apart," he told Al Jazeera.
"The situation speaks volumes about the difficulty of trying to protect any number of sports teams when they're travelling.
"This is one of the big worries concerning South Africa and the World Cup," he said, referring to the upcoming 2010 football tournament.
"This is probably the worst thing that could have happened at the start of the South African World Cup year."
While the attack on the Togo team is certain to send shockwaves, it is not without a precedent.
Only last year, the team bus carrying the Sri Lankan cricket team was attacked in the Pakistani city of Lahore. Several players were injured in the brazen attack.