Hello from CNN, I'm Joe Beck, with the five things you need to know for Wednesday, May 7th.

India and Pakistan are on the brink of an all-out war, raising concerns of further escalation between the nuclear-armed rivals.

India says it's hit, quote, terrorist infrastructure in both Pakistan and Pakistan

administered Kashmir, with its deepest strikes into the country in 50 years. Pakistan says

dozens of people were killed and has vowed retaliation, claiming it shot down five Indian

Air Force jets, as well as a drone, which India has not confirmed.

An Indian defence source says Pakistani shelling has killed several people.

The escalation comes after gunmen massacred more than two dozen civilians, mostly tourists,

in Indian-controlled Kashmir last month.

India accused Pakistan of being involved, which Islamabad denies.

CNN's Paula Hancock has more.

Well, Joe, India and Pakistan have a long history of conflict.

They both control parts of Kashmir, a flashpoint in their relations,

but both claim the territory in full.

It has become one of the most militarized places in the world.

Pakistan's Prime Minister has called India's early morning strikes an act of war, but India claims it showed considerable restraint.

And now the US, China, the UN are all calling on both countries to prevent

further escalation.

The conclave to select a new Pope has started at the Vatican today. Before voting begins,

the College of Cardinals have gathered for a special mass in St. Peter's Basilica.

So what happens next?

Here's CNN's Ben Wiederman.

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