Andy Smith
Mine action specialist

Mined area Indicators – Angola: Informal warning signs



Sheet 5     Informal warning signs
(Page 1)

When local people believe an area to be dangerous or find a device, they often mark it in informal ways so that others will know it is there. The picture shows two examples of improvised warning signs.

A - The picture on the left shows the underside of a train that was ambushed during the war. To prevent the carriages being removed, they were mined. A local person has written a chalk warning sign on the underside of the train.
A lever from a Russian F-1 grenade in the foreground is an indication that soldiers have been in the area since the train was wrecked.

Suggested message(s):

  • Local people may improvise signs themselves.
  • Wrecks that have not been broken up for materials should always be avoided.

B - The picture on the right shows a piece of red cloth tied to a branch. On the ground beneath the cloth you can see the fuze and part of a fallen POMZ mine. The mine was originally laid on a wooden stake with a tripwire attached. The wire may still be in one piece under the leaves and debris.

Suggested message(s):

  • Improvised warning signs are quite common and do not always follow the format recommended by Mine Action workers.
  • People should be aware of improvised signs that might indicate danger and ignore any impulse to investigate them.

 Sheet 6     Informal warning signs
(Page 2)

The picture shows two further examples of improvised warning signs.

The picture on the left shows a dirt road that has not been maintained for a long time. A pair of sticks have been bound together with grass and laid on the ground in a cross. This is an improvised warning of something dangerous in the area. On the right of the picture is a TM57 tank mine that the road's erosion has partly uncovered.

The recommended warning sign is of a pair of crossed sticks standing up. The road in the picture is far too hard for anyone to drive sticks into it without special tools. This is often true even on ground that is not a road.

Suggested message(s):

  • Roads that are not maintained may be dangerous.
  • Crossed sticks may be used as a warning sign.
  • Crossed sticks are more likely to be lying down than standing up.
  • Warning signs may be placed at a distance from the dangerous item. You may have passed the item when you see them.
  • Even when you see a warning sign, you may not see the dangerous item.

The picture on the right shows a little used path in an area where few people live. Someone has placed a square of sticks beside the path.

In the middle of the square of sticks, the top of a PMN-2 pressure mine can just be seen. Made in the former USSR , the PMN-2 is 120mm in diameter (about 4¾”).

The mine is armed by twisting and removing a small metal key. This breaks a wire pin and allows the mine to arm. The picture shows a new key and one that has been buried for ten years.

Deminers may find the keys with their detectors as they work. Sometimes keys are discarded in large numbers in a single place after a minefield has been laid. This can be a reliable indicator of one type of mine laid but can be an unreliable indicator of the total numbers that may be found. Also, other mines may have been laid at another time.

Suggested message(s):

  • Sticks may be laid in a rough square around a dangerous item.
  • Improvised warning signs will be made using the materials available.

Sometimes people tie twists of grass, or place a broken branch from a tree as a warning. These are commonly used to warn of a breakdown on a road and are often seen when there is no explosive danger around.


Sheet 7   Informal warning signs
(Page 3)

The picture shows two further examples of improvised warning signs.

The picture on the left shows a pile of rocks on a path that runs close to a broken and abandoned water tower. The area was not mined, but fighting did take place nearby.

The pile of rocks has been placed alongside a mortar bomb.
You can see part of the ridged metal side of the mortar bomb body showing.

Unexploded mortar bombs are not usually dangerous if they are left alone. Their fuzes are unstable and may be found in a very dangerous state. The picture shows a range of mortar fuzes and also the black plastic caps that are discarded when a fuze is screwed onto a mortar bomb. A mortar bomb fuze can easily remove a child’s hand if it explodes.

Suggested message(s):

  • People will use the materials that are easily found to make a warning sign.
  • Anything unusual such as a simple pile of rocks should be treated with caution.
  • Fuzes are small but very dangerous. Never pick them up.

The picture on the right shows a wire fence that was last repaired quite recently. Only a few strands of wire are missing. Beyond the fence is a metal stake under a tree. Beside that stake you can see a PPM-2 pressure mine on the ground. Mines are often laid so that their top is not buried. If the ground is very hard it can be very difficult to bury a mine properly. If the grass will grow up quickly and conceal the mine, a victim is just as likely to tread on it if it is above ground as if it is buried. And if a soldier may have to remove the mines himself later, they are much easier to find on the surface.

Sometimes earth is scattered over the top of mines when they are laid but it washes off in the first rain.

In areas where the undergrowth is low, mines can sometimes be seen if you know what to look for.

The PPM-2 is a plastic cased anti-personnel mine about 134mm in diameter (5¼”). The picture shows the arming-pin that may be discarded when the mine is laid. It also shows the interior of the mine with a large metal content that makes it easy to find with a good metal detector. 

Suggested message(s):

  • Avoid fenced areas because they may be mined on both sides.
  • If there is a path, use it and always look around for clues of danger. You may be lucky and see something before you step on it.


Mined area
warning signs


Areas without




Roads in
rural areas



Improvised devices
on roads


Surveyor's stick


Fighter plane


grazing land















Angola bush









bush 2







How mines


Other common
AP mines


Other common


Other common