package libprocps4 2:3.3.10-4ubuntu2.3 failed to install/upgrade: unable to securely remove '/usr/share/doc/libprocps4/NEWS.Debian.gz.dpkg-new': Read-only file system

I booted after I detected that '/' has been mounted read only.
After the reboot the crash reporter appeared, and here I am...

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: libprocps4 2:3.3.10-4ubuntu2.3
ProcVersionSignature: Ubuntu 4.4.0-127.153-generic 4.4.128
Uname: Linux 4.4.0-127-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.17
AptOrdering:
 libprocps4: Install
 procps: Install
 libprocps4: Configure
 procps: Configure
 NULL: ConfigurePending
Architecture: amd64
Date: Thu May 24 08:20:15 2018
DpkgTerminalLog:
 Preparing to unpack .../libprocps4_2%3a3.3.10-4ubuntu2.4_amd64.deb ...
 Unpacking libprocps4:amd64 (2:3.3.10-4ubuntu2.4) over (2:3.3.10-4ubuntu2.3) ...
 dpkg: error processing archive /var/cache/apt/archives/libprocps4_2%3a3.3.10-4ubuntu2.4_amd64.deb (--unpack):
  unable to securely remove '/usr/share/doc/libprocps4/NEWS.Debian.gz.dpkg-new': Read-only file system
DuplicateSignature:
 package:libprocps4:2:3.3.10-4ubuntu2.3
 Unpacking libprocps4:amd64 (2:3.3.10-4ubuntu2.4) over (2:3.3.10-4ubuntu2.3) ...
 dpkg: error processing archive /var/cache/apt/archives/libprocps4_2%3a3.3.10-4ubuntu2.4_amd64.deb (--unpack):
  unable to securely remove '/usr/share/doc/libprocps4/NEWS.Debian.gz.dpkg-new': Read-only file system
ErrorMessage: unable to securely remove '/usr/share/doc/libprocps4/NEWS.Debian.gz.dpkg-new': Read-only file system
InstallationDate: Installed on 2016-12-04 (535 days ago)
InstallationMedia: Ubuntu-Server 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.4
 apt 1.2.26
SourcePackage: procps
Title: package libprocps4 2:3.3.10-4ubuntu2.3 failed to install/upgrade: unable to securely remove '/usr/share/doc/libprocps4/NEWS.Debian.gz.dpkg-new': Read-only file system
UpgradeStatus: No upgrade log present (probably fresh install)