5 orphaned blocks in a row?

[jammers]

Hi all,

I've never seen this before, does it happen much?

Blocks mined on: 12/09/2014 Next >>
Height   Time   Relayed By   Hash
320389 (Orphaned)   2014-09-12 23:28:23   Discus Fish   00000000000000000306fb50e8f0f70a25d3b25141eed33caff13804c4fcdeed
320388 (Orphaned)   2014-09-12 23:16:55   62.210.125.106   00000000000000000d31f0c5a390384f2f47a4ab2933f34973e568ca15b11bc0
320387 (Orphaned)   2014-09-12 23:18:08   GHash.IO   00000000000000000c01c3d522c188103f22fb4cd205701133a9aca9a0912a98
320386 (Orphaned)   2014-09-12 23:16:11   Discus Fish   0000000000000000252e52a20d1f01cd0098b109d6d9c45fa86e42dd2204b3a2
320385 (Orphaned)   2014-09-12 23:11:54   Unknown with 1AcAj9p Address   00000000000000000c06e54c51c91aa306f1d043c05ef36afff446041243babb
320384 (Main Chain)   2014-09-12 22:50:50   KnCMiner   00000000000000000c5d9b233c06ce92cf241fc32599c4b2a17368d658e35ee5
320383 (Main Chain)   2014-09-12 22:32:17   Discus Fish   00000000000000001e1e4c73f3bb386191ea8b1fd919bed4a63defec4c9a4659
320382 (Main Chain)   2014-09-12 22:21:35   85.25.195.79   00000000000000000d817ee731a9b93dedd5d3d03ba2c0b3052e7c6fbcc780c5
320381 (Main Chain)   2014-09-12 22:17:35   Discus Fish   00000000000000001545846602a0fd084b5ff985b05d9015bcf764e308a0fadc
320380 (Main Chain)   2014-09-12 22:09:54   GHash.IO   000000000000000011eb3c1fe54cc4ecd126a2c15bbecf54eca2257ed0c08406
320379 (Main Chain)   2014-09-12 21:57:52   Megabigpower   000000000000000001e1db25e11f716a21654a425cc0a54e48261fca9c9a4f86
320378 (Main Chain)   2014-09-12 21:56:03   Unknown with 1AcAj9p Address   00000000000000000fff1e89e13b8570395da9b988fbfb55010bf2f261fa8130
320377 (Main Chain)   2014-09-12 21:47:33   KnCMiner   00000000000000001b7553de4c86bfcdfc996576ac462f4bcbfbd73d989944bc
320376 (Main Chain)   2014-09-12 21:37:39   Slush   000000000000000022ac22a5cd0b2e5ea5bf253ce8d3289af8882b3205e83f0e

I mean five in a row, what could cause that to happen?

[Remember remember the 5th of November]

I think this is a bug in BC.I, blockr.io displays them correctly.

[trout]

most likely  a bug of blockchain.info

5 blocks in a row orphaned means that there is an alternative chain of at least 6 blocks,
which is nowhere to be seen. Had it been present it'd really look like a fork.