There’s growing alarm in East Africa about huge swarms of desert locusts which are spreading across the region.

One swarm in Kenya was reported to be 40km (25 miles) wide.

Huge swarms of desert locusts have invaded countries on both sides of the Red Sea, destroying vegetation.

The Food and Agriculture Organization says the crisis threatens food security across the region.

It is warning that the scale of the surge could grow more than 500 times by mid-year if left unchecked.

It’s the worst invasion of desert locusts in the Horn of Africa in 25 years.

Countries are struggling to control them.

Aerial spraying is going on in Kenya and Ethiopia.

Locusts are best dealt with at source but they bred undetected for months in the southern Arab Peninsula – conditions were perfect following the unusual heavy rains late last year.

They then spread to Yemen and Somalia, where instability prevented any meaningful intervention. There are fears now their population could explode and they move west into Uganda and South Sudan.