BBC 6Music made an unplanned visit to the Radio 4 airwaves this evening. Just after 1900, at the end of the hourly news bulletin and just before The Archers, The Undertones were to be heard playing Wednesday Week from their 1980 album Hypnotised. It turned out that an error had been made when 6 Music's output switched from a London studio to Marc Riley's in Manchester and, for two minutes, twenty-three seconds 6Music took over Radio 4 on all frequencies.

Speculation about the cause of the incident was especially feverish on the social nets. On Twitter, miss_s_b wondered:

is it just me, or did 6music just hack radio 4? (tweet)

And tayler voiced the question on many listeners' lips:

Lots of people wondering if the strange music played on Radio 4 at 7 - interrupting the start of The Archers - was a BBC6 Music protest! (tweet)

Diana Speed, the Radio 4 announcer on duty at the time of the takeover, apologised on-air for the interruption and has passed me this official account from her log of events:

R4 Network lost for 2'23" when 6MUSIC was transmitted on our six platforms on the Network Switcher. This was due to a mistake in monitoring when the Control Room did the switch for 6MUSIC from Western House to Manchester at 1900 and instead placed 6MUSIC on our output.I was unaware of loss of network because we monitor desk output in Con and that was going out as normal. Apology was made at the end of the programme.

Listen back to this most unusual upset:

Or download the MP3 here.

In a magnanimous follow-up, Shaun Keaveny played the rare full-length version of Arthur Wood's Barwick Green (The Archers theme) on his breakfast show this morning (followed by The Velvet Underground's Rock & Roll - this week's second-most surreal on-air collision). Listen to the clip from Shaun's show:

Steve Bowbrick is editor of the Radio 4 blog

• Listen again to Marc Riley's 6Music show. Last night's edition of The Archers is now available to listen to - in full - on the Radio 4 web site.
• The story was picked up in The Guardian (who also ran with Radio 4's explanation of the error), The Telegraph and Digital Spy.
• Picture by Aidan Wojtas. Used under licence.