The Microsoft founder urges young innovators to use Artificial Intelligence to improve health services.

One poll has pro-EU candidate Rafal Trzaskowski in the lead, while the other indicates conservative Karol Nawrocki will win.

Watch: Eyewitness captures moments during Colorado attack

The Australian woman has pleaded not guilty to four charges - three of murder and one of attempted murder.

The army says it defended its post "vigorously" but eventually withdrew, as militants seized on their base.

Hamdi al-Najjar's wife and 11-year-old son Adam, who was severely injured, are the only survivors in their family.

The two warring sides remain far apart on how to end the conflict after a second round of talks in Turkey.

The activists hid the waxwork under a blanket before taking it out through an emergency exit, reports say.