A woman claimed yesterday to have seen two balls of lightning in her house in West Wales.

Annie Dobson, from Kidwelly, said she was terrified to see the mysterious phenomena bouncing around her home.

BBC weather presenter Derek Brockway said the incident was very unusual and potentially deadly.

"For years, the very existence of ball lightning was controversial," he said.

"Most scientists now accept that it does occur, but there is still no agreed explanation of what it is.

"One theory suggests that ball lightning is a highly ionised blob of plasma held together by magnetic fields, while an exotic explanation claims the cause is mini black holes created in the big bang.

"Ball lightning appears as a glowing ball of light or sphere that moves slowly near the ground before disappearing or exploding.

"Typically the size of a grapefruit, sometimes it is as small as a pea, or as large as a bus.

"It sometimes hovers but can also bounce along the ground. It usually lasts only a few seconds, but sometimes much longer. Sometimes it disappears silently, other times it explodes violently.

"It contains very high levels of energy. People have been killed by ball lightning.

"Sounds like Annie Dobson was very lucky yesterday."