More than half of the terror attacks in the world in 2016 took place in five countries, including India and Pakistan, a senior US counter-terror official has said.

Justin Siberell, Acting Coordinator for Counterterrorism, in a media briefing on the release of the Country Reports on Terrorism by the US State Department, also said that the total number of terror attacks in 2016 were lower than in 2015.

"And although terrorist attacks took place in 104 countries in 2016, they were heavily concentrated geographically, as they have been for the past several years.

"Fifty-five per cent of all attacks took place in Iraq, Afghanistan, India, Pakistan, and the Philippines, and 75 per cent of all deaths due to terrorist attacks took place in Iraq, Afghanistan, Syria, Nigeria, and Pakistan," Siberell said.

He also said the total number of terrorist attacks in 2016 decreased by 9 per cent, and total deaths due to terrorist attacks decreased by 13 per cent compared to 2015.

"This was largely due to fewer attacks and deaths from terrorist attacks in Afghanistan, Syria, Nigeria, Pakistan, and Yemen. At the same time, there was an increase in terrorist attacks and total deaths in several countries, including Iraq, Somalia, and Turkey."

He said the Islamic State was responsible for more attacks and deaths than any other perpetrator group in 2016. In 2015, it was the Taliban that was responsible for more attacks and deaths.

He pointed out that the statistics were compiled by the University of Maryland and "they are not a US government product".

To a question, Siberell said: "The broad trend, however, is a slight decrease from 2015, and that -- in 2015 had a slight decrease from 2014. 2014, of course, was a year of significant increase -- really a spike, frankly -- in global terrorist attacks due largely to the -- coinciding with the rise of ISIS, vicious attacks in Nigeria conducted by Boko Haram, et cetera."